diff --git a/git/__init__.py b/git/__init__.py
index 58e4e7b65..0514d545b 100644
--- a/git/__init__.py
+++ b/git/__init__.py
@@ -5,9 +5,12 @@
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
 # flake8: noqa
 #@PydevCodeAnalysisIgnore
+import inspect
 import os
 import sys
-import inspect
+
+import os.path as osp
+
 
 __version__ = 'git'
 
@@ -16,7 +19,7 @@
 def _init_externals():
     """Initialize external projects by putting them into the path"""
     if __version__ == 'git':
-        sys.path.insert(0, os.path.join(os.path.dirname(__file__), 'ext', 'gitdb'))
+        sys.path.insert(0, osp.join(osp.dirname(__file__), 'ext', 'gitdb'))
 
     try:
         import gitdb
diff --git a/git/config.py b/git/config.py
index eddfac151..a0b258226 100644
--- a/git/config.py
+++ b/git/config.py
@@ -6,21 +6,13 @@
 """Module containing module parser implementation able to properly read and write
 configuration files"""
 
-import re
-try:
-    import ConfigParser as cp
-except ImportError:
-    # PY3
-    import configparser as cp
+import abc
+from functools import wraps
 import inspect
 import logging
-import abc
 import os
+import re
 
-from functools import wraps
-
-from git.odict import OrderedDict
-from git.util import LockFile
 from git.compat import (
     string_types,
     FileType,
@@ -29,6 +21,18 @@
     with_metaclass,
     PY3
 )
+from git.odict import OrderedDict
+from git.util import LockFile
+
+import os.path as osp
+
+
+try:
+    import ConfigParser as cp
+except ImportError:
+    # PY3
+    import configparser as cp
+
 
 __all__ = ('GitConfigParser', 'SectionConstraint')
 
@@ -408,15 +412,15 @@ def read(self):
             if self._has_includes():
                 for _, include_path in self.items('include'):
                     if include_path.startswith('~'):
-                        include_path = os.path.expanduser(include_path)
-                    if not os.path.isabs(include_path):
+                        include_path = osp.expanduser(include_path)
+                    if not osp.isabs(include_path):
                         if not file_ok:
                             continue
                         # end ignore relative paths if we don't know the configuration file path
-                        assert os.path.isabs(file_path), "Need absolute paths to be sure our cycle checks will work"
-                        include_path = os.path.join(os.path.dirname(file_path), include_path)
+                        assert osp.isabs(file_path), "Need absolute paths to be sure our cycle checks will work"
+                        include_path = osp.join(osp.dirname(file_path), include_path)
                     # end make include path absolute
-                    include_path = os.path.normpath(include_path)
+                    include_path = osp.normpath(include_path)
                     if include_path in seen or not os.access(include_path, os.R_OK):
                         continue
                     seen.add(include_path)
diff --git a/git/index/base.py b/git/index/base.py
index ac2d30190..1e423df45 100644
--- a/git/index/base.py
+++ b/git/index/base.py
@@ -3,34 +3,28 @@
 #
 # This module is part of GitPython and is released under
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
-import tempfile
-import os
-import sys
-import subprocess
 import glob
 from io import BytesIO
-
+import os
 from stat import S_ISLNK
+import subprocess
+import sys
+import tempfile
 
-from .typ import (
-    BaseIndexEntry,
-    IndexEntry,
-)
-
-from .util import (
-    TemporaryFileSwap,
-    post_clear_cache,
-    default_index,
-    git_working_dir
+from git.compat import (
+    izip,
+    xrange,
+    string_types,
+    force_bytes,
+    defenc,
+    mviter,
+    is_win
 )
-
-import git.diff as diff
 from git.exc import (
     GitCommandError,
     CheckoutError,
     InvalidGitRepositoryError
 )
-
 from git.objects import (
     Blob,
     Submodule,
@@ -38,18 +32,7 @@
     Object,
     Commit,
 )
-
 from git.objects.util import Serializable
-from git.compat import (
-    izip,
-    xrange,
-    string_types,
-    force_bytes,
-    defenc,
-    mviter,
-    is_win
-)
-
 from git.util import (
     LazyMixin,
     LockedFD,
@@ -58,6 +41,12 @@
     to_native_path_linux,
     unbare_repo
 )
+from gitdb.base import IStream
+from gitdb.db import MemoryDB
+from gitdb.util import to_bin_sha
+
+import git.diff as diff
+import os.path as osp
 
 from .fun import (
     entry_key,
@@ -69,10 +58,17 @@
     S_IFGITLINK,
     run_commit_hook
 )
+from .typ import (
+    BaseIndexEntry,
+    IndexEntry,
+)
+from .util import (
+    TemporaryFileSwap,
+    post_clear_cache,
+    default_index,
+    git_working_dir
+)
 
-from gitdb.base import IStream
-from gitdb.db import MemoryDB
-from gitdb.util import to_bin_sha
 
 __all__ = ('IndexFile', 'CheckoutError')
 
@@ -354,7 +350,7 @@ def from_tree(cls, repo, *treeish, **kwargs):
             index.entries       # force it to read the file as we will delete the temp-file
             del(index_handler)  # release as soon as possible
         finally:
-            if os.path.exists(tmp_index):
+            if osp.exists(tmp_index):
                 os.remove(tmp_index)
         # END index merge handling
 
@@ -374,8 +370,8 @@ def raise_exc(e):
         rs = r + os.sep
         for path in paths:
             abs_path = path
-            if not os.path.isabs(abs_path):
-                abs_path = os.path.join(r, path)
+            if not osp.isabs(abs_path):
+                abs_path = osp.join(r, path)
             # END make absolute path
 
             try:
@@ -407,7 +403,7 @@ def raise_exc(e):
                 for root, dirs, files in os.walk(abs_path, onerror=raise_exc):  # @UnusedVariable
                     for rela_file in files:
                         # add relative paths only
-                        yield os.path.join(root.replace(rs, ''), rela_file)
+                        yield osp.join(root.replace(rs, ''), rela_file)
                     # END for each file in subdir
                 # END for each subdirectory
             except OSError:
@@ -569,7 +565,7 @@ def _process_diff_args(self, args):
     def _to_relative_path(self, path):
         """:return: Version of path relative to our git directory or raise ValueError
         if it is not within our git direcotory"""
-        if not os.path.isabs(path):
+        if not osp.isabs(path):
             return path
         if self.repo.bare:
             raise InvalidGitRepositoryError("require non-bare repository")
@@ -617,12 +613,12 @@ def _entries_for_paths(self, paths, path_rewriter, fprogress, entries):
         entries_added = list()
         if path_rewriter:
             for path in paths:
-                if os.path.isabs(path):
+                if osp.isabs(path):
                     abspath = path
                     gitrelative_path = path[len(self.repo.working_tree_dir) + 1:]
                 else:
                     gitrelative_path = path
-                    abspath = os.path.join(self.repo.working_tree_dir, gitrelative_path)
+                    abspath = osp.join(self.repo.working_tree_dir, gitrelative_path)
                 # end obtain relative and absolute paths
 
                 blob = Blob(self.repo, Blob.NULL_BIN_SHA,
diff --git a/git/index/fun.py b/git/index/fun.py
index 7a7593fed..d9c0f2153 100644
--- a/git/index/fun.py
+++ b/git/index/fun.py
@@ -1,6 +1,8 @@
 # Contains standalone functions to accompany the index implementation and make it
 # more versatile
 # NOTE: Autodoc hates it if this is a docstring
+from io import BytesIO
+import os
 from stat import (
     S_IFDIR,
     S_IFLNK,
@@ -9,13 +11,18 @@
     S_IFMT,
     S_IFREG,
 )
-
-from io import BytesIO
-import os
 import subprocess
 
-from git.util import IndexFileSHA1Writer, finalize_process
 from git.cmd import PROC_CREATIONFLAGS, handle_process_output
+from git.compat import (
+    PY3,
+    defenc,
+    force_text,
+    force_bytes,
+    is_posix,
+    safe_encode,
+    safe_decode,
+)
 from git.exc import (
     UnmergedEntriesError,
     HookExecutionError
@@ -25,6 +32,11 @@
     traverse_tree_recursive,
     traverse_trees_recursive
 )
+from git.util import IndexFileSHA1Writer, finalize_process
+from gitdb.base import IStream
+from gitdb.typ import str_tree_type
+
+import os.path as osp
 
 from .typ import (
     BaseIndexEntry,
@@ -32,23 +44,11 @@
     CE_NAMEMASK,
     CE_STAGESHIFT
 )
-
 from .util import (
     pack,
     unpack
 )
 
-from gitdb.base import IStream
-from gitdb.typ import str_tree_type
-from git.compat import (
-    PY3,
-    defenc,
-    force_text,
-    force_bytes,
-    is_posix,
-    safe_encode,
-    safe_decode,
-)
 
 S_IFGITLINK = S_IFLNK | S_IFDIR     # a submodule
 CE_NAMEMASK_INV = ~CE_NAMEMASK
@@ -59,7 +59,7 @@
 
 def hook_path(name, git_dir):
     """:return: path to the given named hook in the given git repository directory"""
-    return os.path.join(git_dir, 'hooks', name)
+    return osp.join(git_dir, 'hooks', name)
 
 
 def run_commit_hook(name, index):
diff --git a/git/index/util.py b/git/index/util.py
index ce798851d..3c59b1d8c 100644
--- a/git/index/util.py
+++ b/git/index/util.py
@@ -1,12 +1,14 @@
 """Module containing index utilities"""
+from functools import wraps
+import os
 import struct
 import tempfile
-import os
-
-from functools import wraps
 
 from git.compat import is_win
 
+import os.path as osp
+
+
 __all__ = ('TemporaryFileSwap', 'post_clear_cache', 'default_index', 'git_working_dir')
 
 #{ Aliases
@@ -32,8 +34,8 @@ def __init__(self, file_path):
             pass
 
     def __del__(self):
-        if os.path.isfile(self.tmp_file_path):
-            if is_win and os.path.exists(self.file_path):
+        if osp.isfile(self.tmp_file_path):
+            if is_win and osp.exists(self.file_path):
                 os.remove(self.file_path)
             os.rename(self.tmp_file_path, self.file_path)
         # END temp file exists
diff --git a/git/objects/submodule/base.py b/git/objects/submodule/base.py
index 9bb563d7b..d2c6e0209 100644
--- a/git/objects/submodule/base.py
+++ b/git/objects/submodule/base.py
@@ -1,21 +1,18 @@
-from .util import (
-    mkhead,
-    sm_name,
-    sm_section,
-    SubmoduleConfigParser,
-    find_first_remote_branch
-)
-from git.objects.util import Traversable
-from io import BytesIO                   # need a dict to set bloody .name field
-from git.util import (
-    Iterable,
-    join_path_native,
-    to_native_path_linux,
-    RemoteProgress,
-    rmtree,
-    unbare_repo
-)
+# need a dict to set bloody .name field
+from io import BytesIO
+import logging
+import os
+import stat
+from unittest.case import SkipTest
+import uuid
 
+import git
+from git.cmd import Git
+from git.compat import (
+    string_types,
+    defenc,
+    is_win,
+)
 from git.config import (
     SectionConstraint,
     GitConfigParser,
@@ -26,22 +23,28 @@
     NoSuchPathError,
     RepositoryDirtyError
 )
-from git.compat import (
-    string_types,
-    defenc,
-    is_win,
+from git.objects.base import IndexObject, Object
+from git.objects.util import Traversable
+from git.util import (
+    Iterable,
+    join_path_native,
+    to_native_path_linux,
+    RemoteProgress,
+    rmtree,
+    unbare_repo
 )
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 
-import stat
-import git
+import os.path as osp
+
+from .util import (
+    mkhead,
+    sm_name,
+    sm_section,
+    SubmoduleConfigParser,
+    find_first_remote_branch
+)
 
-import os
-import logging
-import uuid
-from unittest.case import SkipTest
-from git.util import HIDE_WINDOWS_KNOWN_ERRORS
-from git.objects.base import IndexObject, Object
-from git.cmd import Git
 
 __all__ = ["Submodule", "UpdateProgress"]
 
@@ -120,7 +123,7 @@ def _set_cache_(self, attr):
                 self.path = reader.get_value('path')
             except cp.NoSectionError:
                 raise ValueError("This submodule instance does not exist anymore in '%s' file"
-                                 % os.path.join(self.repo.working_tree_dir, '.gitmodules'))
+                                 % osp.join(self.repo.working_tree_dir, '.gitmodules'))
             # end
             self._url = reader.get_value('url')
             # git-python extension values - optional
@@ -181,7 +184,7 @@ def _config_parser(cls, repo, parent_commit, read_only):
         # end hanlde parent_commit
 
         if not repo.bare and parent_matches_head:
-            fp_module = os.path.join(repo.working_tree_dir, cls.k_modules_file)
+            fp_module = osp.join(repo.working_tree_dir, cls.k_modules_file)
         else:
             assert parent_commit is not None, "need valid parent_commit in bare repositories"
             try:
@@ -229,9 +232,9 @@ def _config_parser_constrained(self, read_only):
     @classmethod
     def _module_abspath(cls, parent_repo, path, name):
         if cls._need_gitfile_submodules(parent_repo.git):
-            return os.path.join(parent_repo.git_dir, 'modules', name)
+            return osp.join(parent_repo.git_dir, 'modules', name)
         else:
-            return os.path.join(parent_repo.working_tree_dir, path)
+            return osp.join(parent_repo.working_tree_dir, path)
         # end
 
     @classmethod
@@ -246,10 +249,10 @@ def _clone_repo(cls, repo, url, path, name, **kwargs):
         module_checkout_path = module_abspath
         if cls._need_gitfile_submodules(repo.git):
             kwargs['separate_git_dir'] = module_abspath
-            module_abspath_dir = os.path.dirname(module_abspath)
-            if not os.path.isdir(module_abspath_dir):
+            module_abspath_dir = osp.dirname(module_abspath)
+            if not osp.isdir(module_abspath_dir):
                 os.makedirs(module_abspath_dir)
-            module_checkout_path = os.path.join(repo.working_tree_dir, path)
+            module_checkout_path = osp.join(repo.working_tree_dir, path)
         # end
 
         clone = git.Repo.clone_from(url, module_checkout_path, **kwargs)
@@ -267,7 +270,7 @@ def _to_relative_path(cls, parent_repo, path):
             path = path[:-1]
         # END handle trailing slash
 
-        if os.path.isabs(path):
+        if osp.isabs(path):
             working_tree_linux = to_native_path_linux(parent_repo.working_tree_dir)
             if not path.startswith(working_tree_linux):
                 raise ValueError("Submodule checkout path '%s' needs to be within the parents repository at '%s'"
@@ -291,18 +294,18 @@ def _write_git_file_and_module_config(cls, working_tree_dir, module_abspath):
         :param working_tree_dir: directory to write the .git file into
         :param module_abspath: absolute path to the bare repository
         """
-        git_file = os.path.join(working_tree_dir, '.git')
-        rela_path = os.path.relpath(module_abspath, start=working_tree_dir)
+        git_file = osp.join(working_tree_dir, '.git')
+        rela_path = osp.relpath(module_abspath, start=working_tree_dir)
         if is_win:
-            if os.path.isfile(git_file):
+            if osp.isfile(git_file):
                 os.remove(git_file)
         with open(git_file, 'wb') as fp:
             fp.write(("gitdir: %s" % rela_path).encode(defenc))
 
-        with GitConfigParser(os.path.join(module_abspath, 'config'),
+        with GitConfigParser(osp.join(module_abspath, 'config'),
                              read_only=False, merge_includes=False) as writer:
             writer.set_value('core', 'worktree',
-                             to_native_path_linux(os.path.relpath(working_tree_dir, start=module_abspath)))
+                             to_native_path_linux(osp.relpath(working_tree_dir, start=module_abspath)))
 
     #{ Edit Interface
 
@@ -501,7 +504,7 @@ def update(self, recursive=False, init=True, to_latest_revision=False, progress=
 
                 # there is no git-repository yet - but delete empty paths
                 checkout_module_abspath = self.abspath
-                if not dry_run and os.path.isdir(checkout_module_abspath):
+                if not dry_run and osp.isdir(checkout_module_abspath):
                     try:
                         os.rmdir(checkout_module_abspath)
                     except OSError:
@@ -671,7 +674,7 @@ def move(self, module_path, configuration=True, module=True):
         # END handle no change
 
         module_checkout_abspath = join_path_native(self.repo.working_tree_dir, module_checkout_path)
-        if os.path.isfile(module_checkout_abspath):
+        if osp.isfile(module_checkout_abspath):
             raise ValueError("Cannot move repository onto a file: %s" % module_checkout_abspath)
         # END handle target files
 
@@ -684,12 +687,12 @@ def move(self, module_path, configuration=True, module=True):
 
         # remove existing destination
         if module:
-            if os.path.exists(module_checkout_abspath):
+            if osp.exists(module_checkout_abspath):
                 if len(os.listdir(module_checkout_abspath)):
                     raise ValueError("Destination module directory was not empty")
                 # END handle non-emptiness
 
-                if os.path.islink(module_checkout_abspath):
+                if osp.islink(module_checkout_abspath):
                     os.remove(module_checkout_abspath)
                 else:
                     os.rmdir(module_checkout_abspath)
@@ -704,11 +707,11 @@ def move(self, module_path, configuration=True, module=True):
         # move the module into place if possible
         cur_path = self.abspath
         renamed_module = False
-        if module and os.path.exists(cur_path):
+        if module and osp.exists(cur_path):
             os.renames(cur_path, module_checkout_abspath)
             renamed_module = True
 
-            if os.path.isfile(os.path.join(module_checkout_abspath, '.git')):
+            if osp.isfile(osp.join(module_checkout_abspath, '.git')):
                 module_abspath = self._module_abspath(self.repo, self.path, self.name)
                 self._write_git_file_and_module_config(module_checkout_abspath, module_abspath)
             # end handle git file rewrite
@@ -804,11 +807,11 @@ def remove(self, module=True, force=False, configuration=True, dry_run=False):
                 # state. Delete the .git folders last, start with the submodules first
                 mp = self.abspath
                 method = None
-                if os.path.islink(mp):
+                if osp.islink(mp):
                     method = os.remove
-                elif os.path.isdir(mp):
+                elif osp.isdir(mp):
                     method = rmtree
-                elif os.path.exists(mp):
+                elif osp.exists(mp):
                     raise AssertionError("Cannot forcibly delete repository as it was neither a link, nor a directory")
                 # END handle brutal deletion
                 if not dry_run:
@@ -865,7 +868,7 @@ def remove(self, module=True, force=False, configuration=True, dry_run=False):
                 # END delete tree if possible
             # END handle force
 
-            if not dry_run and os.path.isdir(git_dir):
+            if not dry_run and osp.isdir(git_dir):
                 self._clear_cache()
                 try:
                     rmtree(git_dir)
diff --git a/git/refs/symbolic.py b/git/refs/symbolic.py
index ebaff8ca4..d1c412c87 100644
--- a/git/refs/symbolic.py
+++ b/git/refs/symbolic.py
@@ -1,5 +1,9 @@
 import os
 
+from git.compat import (
+    string_types,
+    defenc
+)
 from git.objects import Object, Commit
 from git.util import (
     join_path,
@@ -7,7 +11,6 @@
     to_native_path_linux,
     assure_directory_exists
 )
-
 from gitdb.exc import (
     BadObject,
     BadName
@@ -22,13 +25,12 @@
     hex_to_bin,
     LockedFD
 )
-from git.compat import (
-    string_types,
-    defenc
-)
+
+import os.path as osp
 
 from .log import RefLog
 
+
 __all__ = ["SymbolicReference"]
 
 
@@ -458,7 +460,7 @@ def delete(cls, repo, path):
 
         # delete the reflog
         reflog_path = RefLog.path(cls(repo, full_ref_path))
-        if os.path.isfile(reflog_path):
+        if osp.isfile(reflog_path):
             os.remove(reflog_path)
         # END remove reflog
 
diff --git a/git/repo/base.py b/git/repo/base.py
index 6355615e8..af923bdec 100644
--- a/git/repo/base.py
+++ b/git/repo/base.py
@@ -10,12 +10,6 @@
 import re
 import sys
 
-from gitdb.util import (
-    join,
-    isfile,
-    hex_to_bin
-)
-
 from git.cmd import (
     Git,
     handle_process_output
@@ -36,6 +30,13 @@
 from git.refs import HEAD, Head, Reference, TagReference
 from git.remote import Remote, add_progress, to_progress_instance
 from git.util import Actor, finalize_process, decygpath
+from gitdb.util import (
+    join,
+    isfile,
+    hex_to_bin
+)
+
+import os.path as osp
 
 from .fun import rev_parse, is_git_dir, find_git_dir, touch
 
@@ -54,7 +55,7 @@
 
 
 def _expand_path(p):
-    return os.path.abspath(os.path.expandvars(os.path.expanduser(p)))
+    return osp.abspath(osp.expandvars(osp.expanduser(p)))
 
 
 class Repo(object):
@@ -100,7 +101,7 @@ def __init__(self, path=None, odbt=DefaultDBType, search_parent_directories=Fals
                 repo = Repo("$REPOSITORIES/Development/git-python.git")
 
             In *Cygwin*, path may be a `'cygdrive/...'` prefixed path.
-            
+
         :param odbt:
             Object DataBase type - a type which is constructed by providing
             the directory containing the database objects, i.e. .git/objects. It will
@@ -118,7 +119,7 @@ def __init__(self, path=None, odbt=DefaultDBType, search_parent_directories=Fals
 
         epath = _expand_path(path or os.getcwd())
         self.git = None  # should be set for __del__ not to fail in case we raise
-        if not os.path.exists(epath):
+        if not osp.exists(epath):
             raise NoSuchPathError(epath)
 
         self.working_dir = None
@@ -128,24 +129,24 @@ def __init__(self, path=None, odbt=DefaultDBType, search_parent_directories=Fals
 
         # walk up the path to find the .git dir
         while curpath:
-            # ABOUT os.path.NORMPATH
+            # ABOUT osp.NORMPATH
             # It's important to normalize the paths, as submodules will otherwise initialize their
             # repo instances with paths that depend on path-portions that will not exist after being
             # removed. It's just cleaner.
             if is_git_dir(curpath):
-                self.git_dir = os.path.normpath(curpath)
-                self._working_tree_dir = os.path.dirname(self.git_dir)
+                self.git_dir = osp.normpath(curpath)
+                self._working_tree_dir = osp.dirname(self.git_dir)
                 break
 
             gitpath = find_git_dir(join(curpath, '.git'))
             if gitpath is not None:
-                self.git_dir = os.path.normpath(gitpath)
+                self.git_dir = osp.normpath(gitpath)
                 self._working_tree_dir = curpath
                 break
 
             if not search_parent_directories:
                 break
-            curpath, dummy = os.path.split(curpath)
+            curpath, dummy = osp.split(curpath)
             if not dummy:
                 break
         # END while curpath
@@ -361,12 +362,12 @@ def _get_config_path(self, config_level):
         if config_level == "system":
             return "/etc/gitconfig"
         elif config_level == "user":
-            config_home = os.environ.get("XDG_CONFIG_HOME") or os.path.join(os.environ.get("HOME", '~'), ".config")
-            return os.path.normpath(os.path.expanduser(join(config_home, "git", "config")))
+            config_home = os.environ.get("XDG_CONFIG_HOME") or osp.join(os.environ.get("HOME", '~'), ".config")
+            return osp.normpath(osp.expanduser(join(config_home, "git", "config")))
         elif config_level == "global":
-            return os.path.normpath(os.path.expanduser("~/.gitconfig"))
+            return osp.normpath(osp.expanduser("~/.gitconfig"))
         elif config_level == "repository":
-            return os.path.normpath(join(self.git_dir, "config"))
+            return osp.normpath(join(self.git_dir, "config"))
 
         raise ValueError("Invalid configuration level: %r" % config_level)
 
@@ -511,11 +512,11 @@ def is_ancestor(self, ancestor_rev, rev):
 
     def _get_daemon_export(self):
         filename = join(self.git_dir, self.DAEMON_EXPORT_FILE)
-        return os.path.exists(filename)
+        return osp.exists(filename)
 
     def _set_daemon_export(self, value):
         filename = join(self.git_dir, self.DAEMON_EXPORT_FILE)
-        fileexists = os.path.exists(filename)
+        fileexists = osp.exists(filename)
         if value and not fileexists:
             touch(filename)
         elif not value and fileexists:
@@ -532,7 +533,7 @@ def _get_alternates(self):
         :return: list of strings being pathnames of alternates"""
         alternates_path = join(self.git_dir, 'objects', 'info', 'alternates')
 
-        if os.path.exists(alternates_path):
+        if osp.exists(alternates_path):
             with open(alternates_path, 'rb') as f:
                 alts = f.read().decode(defenc)
             return alts.strip().splitlines()
@@ -841,7 +842,7 @@ def init(cls, path=None, mkdir=True, odbt=DefaultDBType, **kwargs):
         :return: ``git.Repo`` (the newly created repo)"""
         if path:
             path = _expand_path(path)
-        if mkdir and path and not os.path.exists(path):
+        if mkdir and path and not osp.exists(path):
             os.makedirs(path, 0o755)
 
         # git command automatically chdir into the directory
@@ -879,7 +880,7 @@ def _clone(cls, git, url, path, odb_default_type, progress, **kwargs):
 
         # our git command could have a different working dir than our actual
         # environment, hence we prepend its working dir if required
-        if not os.path.isabs(path) and git.working_dir:
+        if not osp.isabs(path) and git.working_dir:
             path = join(git._working_dir, path)
 
         # adjust remotes - there may be operating systems which use backslashes,
@@ -958,7 +959,7 @@ def has_separate_working_tree(self):
         """
         if self.bare:
             return False
-        return os.path.isfile(os.path.join(self.working_tree_dir, '.git'))
+        return osp.isfile(osp.join(self.working_tree_dir, '.git'))
 
     rev_parse = rev_parse
 
diff --git a/git/repo/fun.py b/git/repo/fun.py
index 320eb1c8d..c770fd43b 100644
--- a/git/repo/fun.py
+++ b/git/repo/fun.py
@@ -2,12 +2,14 @@
 import os
 from string import digits
 
+from git.compat import xrange
+from git.exc import WorkTreeRepositoryUnsupported
+from git.objects import Object
+from git.refs import SymbolicReference
 from gitdb.exc import (
     BadObject,
     BadName,
 )
-from git.refs import SymbolicReference
-from git.objects import Object
 from gitdb.util import (
     join,
     isdir,
@@ -16,8 +18,8 @@
     hex_to_bin,
     bin_to_hex
 )
-from git.exc import WorkTreeRepositoryUnsupported
-from git.compat import xrange
+
+import os.path as osp
 
 
 __all__ = ('rev_parse', 'is_git_dir', 'touch', 'find_git_dir', 'name_to_object', 'short_to_long', 'deref_tag',
@@ -42,7 +44,7 @@ def is_git_dir(d):
         if isdir(join(d, 'objects')) and isdir(join(d, 'refs')):
             headref = join(d, 'HEAD')
             return isfile(headref) or \
-                (os.path.islink(headref) and
+                (osp.islink(headref) and
                  os.readlink(headref).startswith('refs'))
         elif isfile(join(d, 'gitdir')) and isfile(join(d, 'commondir')) and isfile(join(d, 'gitfile')):
             raise WorkTreeRepositoryUnsupported(d)
@@ -62,7 +64,7 @@ def find_git_dir(d):
     else:
         if content.startswith('gitdir: '):
             path = content[8:]
-            if not os.path.isabs(path):
+            if not osp.isabs(path):
                 path = join(dirname(d), path)
             return find_git_dir(path)
     # end handle exception
diff --git a/git/test/performance/lib.py b/git/test/performance/lib.py
index b57b9b714..700fee98f 100644
--- a/git/test/performance/lib.py
+++ b/git/test/performance/lib.py
@@ -1,21 +1,23 @@
 """Contains library functions"""
+import logging
 import os
-from git.test.lib import (
-    TestBase
-)
 import tempfile
-import logging
 
+from git import (
+    Repo
+)
 from git.db import (
     GitCmdObjectDB,
     GitDB
 )
-
-from git import (
-    Repo
+from git.test.lib import (
+    TestBase
 )
 from git.util import rmtree
 
+import os.path as osp
+
+
 #{ Invvariants
 k_env_git_repo = "GIT_PYTHON_TEST_GIT_REPO_BASE"
 
@@ -52,7 +54,7 @@ def setUp(self):
             logging.info(
                 ("You can set the %s environment variable to a .git repository of" % k_env_git_repo) +
                 "your choice - defaulting to the gitpython repository")
-            repo_path = os.path.dirname(__file__)
+            repo_path = osp.dirname(__file__)
         # end set some repo path
         self.gitrorepo = Repo(repo_path, odbt=GitCmdObjectDB, search_parent_directories=True)
         self.puregitrorepo = Repo(repo_path, odbt=GitDB, search_parent_directories=True)
diff --git a/git/test/performance/test_streams.py b/git/test/performance/test_streams.py
index 42cbade5b..699aa25b1 100644
--- a/git/test/performance/test_streams.py
+++ b/git/test/performance/test_streams.py
@@ -1,26 +1,27 @@
 """Performance data streaming performance"""
 from __future__ import print_function
 
-from time import time
 import os
-import sys
 import subprocess
+import sys
+from time import time
 
 from git.test.lib import (
     with_rw_repo
 )
-from gitdb.util import bin_to_hex
+from gitdb import (
+    LooseObjectDB,
+    IStream
+)
 from gitdb.test.lib import make_memory_file
+from gitdb.util import bin_to_hex
+
+import os.path as osp
 
 from .lib import (
     TestBigRepoR
 )
 
-from gitdb import (
-    LooseObjectDB,
-    IStream
-)
-
 
 class TestObjDBPerformance(TestBigRepoR):
 
@@ -31,7 +32,7 @@ class TestObjDBPerformance(TestBigRepoR):
     def test_large_data_streaming(self, rwrepo):
         # TODO: This part overlaps with the same file in gitdb.test.performance.test_stream
         # It should be shared if possible
-        ldb = LooseObjectDB(os.path.join(rwrepo.git_dir, 'objects'))
+        ldb = LooseObjectDB(osp.join(rwrepo.git_dir, 'objects'))
 
         for randomize in range(2):
             desc = (randomize and 'random ') or ''
@@ -47,7 +48,7 @@ def test_large_data_streaming(self, rwrepo):
             elapsed_add = time() - st
             assert ldb.has_object(binsha)
             db_file = ldb.readable_db_object_path(bin_to_hex(binsha))
-            fsize_kib = os.path.getsize(db_file) / 1000
+            fsize_kib = osp.getsize(db_file) / 1000
 
             size_kib = size / 1000
             msg = "Added %i KiB (filesize = %i KiB) of %s data to loose odb in %f s ( %f Write KiB / s)"
@@ -109,7 +110,7 @@ def test_large_data_streaming(self, rwrepo):
             assert gitsha == bin_to_hex(binsha)     # we do it the same way, right ?
 
             #  as its the same sha, we reuse our path
-            fsize_kib = os.path.getsize(db_file) / 1000
+            fsize_kib = osp.getsize(db_file) / 1000
             msg = "Added %i KiB (filesize = %i KiB) of %s data to using git-hash-object in %f s ( %f Write KiB / s)"
             msg %= (size_kib, fsize_kib, desc, gelapsed_add, size_kib / gelapsed_add)
             print(msg, file=sys.stderr)
diff --git a/git/test/test_base.py b/git/test/test_base.py
index 7fc3096f3..576df9613 100644
--- a/git/test/test_base.py
+++ b/git/test/test_base.py
@@ -9,22 +9,24 @@
 import tempfile
 from unittest import skipIf
 
-import git.objects.base as base
-from git.test.lib import (
-    TestBase,
-    assert_raises,
-    with_rw_repo,
-    with_rw_and_rw_remote_repo
-)
 from git import (
     Blob,
     Tree,
     Commit,
     TagObject
 )
+from git.compat import is_win
 from git.objects.util import get_object_type_by_name
+from git.test.lib import (
+    TestBase,
+    assert_raises,
+    with_rw_repo,
+    with_rw_and_rw_remote_repo
+)
 from gitdb.util import hex_to_bin
-from git.compat import is_win
+
+import git.objects.base as base
+import os.path as osp
 
 
 class TestBase(TestBase):
@@ -103,19 +105,19 @@ def test_object_resolution(self):
     @with_rw_repo('HEAD', bare=True)
     def test_with_bare_rw_repo(self, bare_rw_repo):
         assert bare_rw_repo.config_reader("repository").getboolean("core", "bare")
-        assert os.path.isfile(os.path.join(bare_rw_repo.git_dir, 'HEAD'))
+        assert osp.isfile(osp.join(bare_rw_repo.git_dir, 'HEAD'))
 
     @with_rw_repo('0.1.6')
     def test_with_rw_repo(self, rw_repo):
         assert not rw_repo.config_reader("repository").getboolean("core", "bare")
-        assert os.path.isdir(os.path.join(rw_repo.working_tree_dir, 'lib'))
+        assert osp.isdir(osp.join(rw_repo.working_tree_dir, 'lib'))
 
     #@skipIf(HIDE_WINDOWS_FREEZE_ERRORS, "FIXME: Freezes!  sometimes...")
     @with_rw_and_rw_remote_repo('0.1.6')
     def test_with_rw_remote_and_rw_repo(self, rw_repo, rw_remote_repo):
         assert not rw_repo.config_reader("repository").getboolean("core", "bare")
         assert rw_remote_repo.config_reader("repository").getboolean("core", "bare")
-        assert os.path.isdir(os.path.join(rw_repo.working_tree_dir, 'lib'))
+        assert osp.isdir(osp.join(rw_repo.working_tree_dir, 'lib'))
 
     @skipIf(sys.version_info < (3,) and is_win,
             "Unicode woes, see https://github.com/gitpython-developers/GitPython/pull/519")
@@ -123,7 +125,7 @@ def test_with_rw_remote_and_rw_repo(self, rw_repo, rw_remote_repo):
     def test_add_unicode(self, rw_repo):
         filename = u"שלום.txt"
 
-        file_path = os.path.join(rw_repo.working_dir, filename)
+        file_path = osp.join(rw_repo.working_dir, filename)
 
         # verify first that we could encode file name in this environment
         try:
diff --git a/git/test/test_commit.py b/git/test/test_commit.py
index fd9777fb8..fbb1c244e 100644
--- a/git/test/test_commit.py
+++ b/git/test/test_commit.py
@@ -6,34 +6,36 @@
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
 from __future__ import print_function
 
-from git.test.lib import (
-    TestBase,
-    assert_equal,
-    assert_not_equal,
-    with_rw_repo,
-    fixture_path,
-    StringProcessAdapter
-)
+from datetime import datetime
+from io import BytesIO
+import re
+import sys
+import time
+
 from git import (
     Commit,
     Actor,
 )
-from gitdb import IStream
-from git.test.lib import with_rw_directory
+from git import Repo
 from git.compat import (
     string_types,
     text_type
 )
-from git import Repo
+from git.objects.util import tzoffset, utc
 from git.repo.fun import touch
+from git.test.lib import (
+    TestBase,
+    assert_equal,
+    assert_not_equal,
+    with_rw_repo,
+    fixture_path,
+    StringProcessAdapter
+)
+from git.test.lib import with_rw_directory
+from gitdb import IStream
+
+import os.path as osp
 
-from io import BytesIO
-import time
-import sys
-import re
-import os
-from datetime import datetime
-from git.objects.util import tzoffset, utc
 
 try:
     from unittest.mock import Mock
@@ -232,8 +234,8 @@ def test_rev_list_bisect_all(self):
 
     @with_rw_directory
     def test_ambiguous_arg_iteration(self, rw_dir):
-        rw_repo = Repo.init(os.path.join(rw_dir, 'test_ambiguous_arg'))
-        path = os.path.join(rw_repo.working_tree_dir, 'master')
+        rw_repo = Repo.init(osp.join(rw_dir, 'test_ambiguous_arg'))
+        path = osp.join(rw_repo.working_tree_dir, 'master')
         touch(path)
         rw_repo.index.add([path])
         rw_repo.index.commit('initial commit')
diff --git a/git/test/test_config.py b/git/test/test_config.py
index 32873f243..0dfadda64 100644
--- a/git/test/test_config.py
+++ b/git/test/test_config.py
@@ -6,7 +6,6 @@
 
 import glob
 import io
-import os
 
 from git import (
     GitConfigParser
@@ -91,7 +90,7 @@ def test_read_write(self):
 
     @with_rw_directory
     def test_lock_reentry(self, rw_dir):
-        fpl = os.path.join(rw_dir, 'l')
+        fpl = osp.join(rw_dir, 'l')
         gcp = GitConfigParser(fpl, read_only=False)
         with gcp as cw:
             cw.set_value('include', 'some_value', 'a')
@@ -103,7 +102,7 @@ def test_lock_reentry(self, rw_dir):
                 GitConfigParser(fpl, read_only=False)
         # but work when the lock is removed
         with GitConfigParser(fpl, read_only=False):
-            assert os.path.exists(fpl)
+            assert osp.exists(fpl)
             # reentering with an existing lock must fail due to exclusive access
             with self.assertRaises(IOError):
                 gcp.__enter__()
@@ -178,17 +177,17 @@ def check_test_value(cr, value):
         # end
 
         # PREPARE CONFIG FILE A
-        fpa = os.path.join(rw_dir, 'a')
+        fpa = osp.join(rw_dir, 'a')
         with GitConfigParser(fpa, read_only=False) as cw:
             write_test_value(cw, 'a')
 
-            fpb = os.path.join(rw_dir, 'b')
-            fpc = os.path.join(rw_dir, 'c')
+            fpb = osp.join(rw_dir, 'b')
+            fpc = osp.join(rw_dir, 'c')
             cw.set_value('include', 'relative_path_b', 'b')
             cw.set_value('include', 'doesntexist', 'foobar')
             cw.set_value('include', 'relative_cycle_a_a', 'a')
             cw.set_value('include', 'absolute_cycle_a_a', fpa)
-        assert os.path.exists(fpa)
+        assert osp.exists(fpa)
 
         # PREPARE CONFIG FILE B
         with GitConfigParser(fpb, read_only=False) as cw:
diff --git a/git/test/test_db.py b/git/test/test_db.py
index 5dcf592a8..1741e7b9c 100644
--- a/git/test/test_db.py
+++ b/git/test/test_db.py
@@ -3,17 +3,18 @@
 #
 # This module is part of GitPython and is released under
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
-from git.test.lib import TestBase
 from git.db import GitCmdObjectDB
-from gitdb.util import bin_to_hex
 from git.exc import BadObject
-import os
+from git.test.lib import TestBase
+from gitdb.util import bin_to_hex
+
+import os.path as osp
 
 
 class TestDB(TestBase):
 
     def test_base(self):
-        gdb = GitCmdObjectDB(os.path.join(self.rorepo.git_dir, 'objects'), self.rorepo.git)
+        gdb = GitCmdObjectDB(osp.join(self.rorepo.git_dir, 'objects'), self.rorepo.git)
 
         # partial to complete - works with everything
         hexsha = bin_to_hex(gdb.partial_to_complete_sha_hex("0.1.6"))
diff --git a/git/test/test_diff.py b/git/test/test_diff.py
index d5f5b721b..48a5a641f 100644
--- a/git/test/test_diff.py
+++ b/git/test/test_diff.py
@@ -4,8 +4,15 @@
 #
 # This module is part of GitPython and is released under
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
-import os
-
+import ddt
+from git import (
+    Repo,
+    GitCommandError,
+    Diff,
+    DiffIndex,
+    NULL_TREE,
+)
+from git.cmd import Git
 from git.test.lib import (
     TestBase,
     StringProcessAdapter,
@@ -14,18 +21,9 @@
     assert_true,
 
 )
-
 from git.test.lib import with_rw_directory
 
-from git import (
-    Repo,
-    GitCommandError,
-    Diff,
-    DiffIndex,
-    NULL_TREE,
-)
-import ddt
-from git.cmd import Git
+import os.path as osp
 
 
 @ddt.ddt
@@ -54,7 +52,7 @@ def _assert_diff_format(self, diffs):
     def test_diff_with_staged_file(self, rw_dir):
         # SETUP INDEX WITH MULTIPLE STAGES
         r = Repo.init(rw_dir)
-        fp = os.path.join(rw_dir, 'hello.txt')
+        fp = osp.join(rw_dir, 'hello.txt')
         with open(fp, 'w') as fs:
             fs.write("hello world")
         r.git.add(Git.polish_url(fp))
diff --git a/git/test/test_docs.py b/git/test/test_docs.py
index f3c75f79f..bb937d93c 100644
--- a/git/test/test_docs.py
+++ b/git/test/test_docs.py
@@ -9,6 +9,8 @@
 from git.test.lib import TestBase
 from git.test.lib.helper import with_rw_directory
 
+import os.path as osp
+
 
 class Tutorials(TestBase):
 
@@ -23,7 +25,7 @@ def tearDown(self):
     def test_init_repo_object(self, rw_dir):
         # [1-test_init_repo_object]
         from git import Repo
-        join = os.path.join
+        join = osp.join
 
         # rorepo is a Repo instance pointing to the git-python repository.
         # For all you know, the first argument to Repo is a path to the repository
@@ -62,7 +64,7 @@ def test_init_repo_object(self, rw_dir):
 
         # repository paths
         # [7-test_init_repo_object]
-        assert os.path.isdir(cloned_repo.working_tree_dir)                   # directory with your work files
+        assert osp.isdir(cloned_repo.working_tree_dir)                   # directory with your work files
         assert cloned_repo.git_dir.startswith(cloned_repo.working_tree_dir)  # directory containing the git repository
         assert bare_repo.working_tree_dir is None                            # bare repositories have no working tree
         # ![7-test_init_repo_object]
@@ -146,7 +148,7 @@ def update(self, op_code, cur_count, max_count=None, message=''):
         self.assertEqual(new_branch.checkout(), cloned_repo.active_branch)     # checking out branch adjusts the wtree
         self.assertEqual(new_branch.commit, past.commit)                       # Now the past is checked out
 
-        new_file_path = os.path.join(cloned_repo.working_tree_dir, 'my-new-file')
+        new_file_path = osp.join(cloned_repo.working_tree_dir, 'my-new-file')
         open(new_file_path, 'wb').close()                             # create new file in working tree
         cloned_repo.index.add([new_file_path])                        # add it to the index
         # Commit the changes to deviate masters history
@@ -162,7 +164,7 @@ def update(self, op_code, cur_count, max_count=None, message=''):
         # now new_branch is ahead of master, which probably should be checked out and reset softly.
         # note that all these operations didn't touch the working tree, as we managed it ourselves.
         # This definitely requires you to know what you are doing :) !
-        assert os.path.basename(new_file_path) in new_branch.commit.tree  # new file is now in tree
+        assert osp.basename(new_file_path) in new_branch.commit.tree  # new file is now in tree
         master.commit = new_branch.commit            # let master point to most recent commit
         cloned_repo.head.reference = master          # we adjusted just the reference, not the working tree or index
         # ![13-test_init_repo_object]
@@ -192,7 +194,7 @@ def update(self, op_code, cur_count, max_count=None, message=''):
     def test_references_and_objects(self, rw_dir):
         # [1-test_references_and_objects]
         import git
-        repo = git.Repo.clone_from(self._small_repo_url(), os.path.join(rw_dir, 'repo'), branch='master')
+        repo = git.Repo.clone_from(self._small_repo_url(), osp.join(rw_dir, 'repo'), branch='master')
 
         heads = repo.heads
         master = heads.master       # lists can be accessed by name for convenience
@@ -264,7 +266,7 @@ def test_references_and_objects(self, rw_dir):
 
         # [11-test_references_and_objects]
         hct.blobs[0].data_stream.read()        # stream object to read data from
-        hct.blobs[0].stream_data(open(os.path.join(rw_dir, 'blob_data'), 'wb'))  # write data to given stream
+        hct.blobs[0].stream_data(open(osp.join(rw_dir, 'blob_data'), 'wb'))  # write data to given stream
         # ![11-test_references_and_objects]
 
         # [12-test_references_and_objects]
@@ -350,11 +352,11 @@ def test_references_and_objects(self, rw_dir):
         # Access blob objects
         for (path, stage), entry in index.entries.items():  # @UnusedVariable
             pass
-        new_file_path = os.path.join(repo.working_tree_dir, 'new-file-name')
+        new_file_path = osp.join(repo.working_tree_dir, 'new-file-name')
         open(new_file_path, 'w').close()
         index.add([new_file_path])                                             # add a new file to the index
         index.remove(['LICENSE'])                                              # remove an existing one
-        assert os.path.isfile(os.path.join(repo.working_tree_dir, 'LICENSE'))  # working tree is untouched
+        assert osp.isfile(osp.join(repo.working_tree_dir, 'LICENSE'))  # working tree is untouched
 
         self.assertEqual(index.commit("my commit message").type, 'commit')              # commit changed index
         repo.active_branch.commit = repo.commit('HEAD~1')                      # forget last commit
@@ -373,11 +375,11 @@ def test_references_and_objects(self, rw_dir):
         # merge two trees three-way into memory
         merge_index = IndexFile.from_tree(repo, 'HEAD~10', 'HEAD', repo.merge_base('HEAD~10', 'HEAD'))
         # and persist it
-        merge_index.write(os.path.join(rw_dir, 'merged_index'))
+        merge_index.write(osp.join(rw_dir, 'merged_index'))
         # ![24-test_references_and_objects]
 
         # [25-test_references_and_objects]
-        empty_repo = git.Repo.init(os.path.join(rw_dir, 'empty'))
+        empty_repo = git.Repo.init(osp.join(rw_dir, 'empty'))
         origin = empty_repo.create_remote('origin', repo.remotes.origin.url)
         assert origin.exists()
         assert origin == empty_repo.remotes.origin == empty_repo.remotes['origin']
@@ -480,8 +482,8 @@ def test_submodules(self):
     def test_add_file_and_commit(self, rw_dir):
         import git
 
-        repo_dir = os.path.join(rw_dir, 'my-new-repo')
-        file_name = os.path.join(repo_dir, 'new-file')
+        repo_dir = osp.join(rw_dir, 'my-new-repo')
+        file_name = osp.join(repo_dir, 'new-file')
 
         r = git.Repo.init(repo_dir)
         # This function just creates an empty file ...
diff --git a/git/test/test_git.py b/git/test/test_git.py
index bd8ebee2c..7d7130225 100644
--- a/git/test/test_git.py
+++ b/git/test/test_git.py
@@ -5,9 +5,17 @@
 # This module is part of GitPython and is released under
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
 import os
-import sys
 import subprocess
+import sys
 
+from git import (
+    Git,
+    GitCommandError,
+    GitCommandNotFound,
+    Repo,
+    cmd
+)
+from git.compat import PY3, is_darwin
 from git.test.lib import (
     TestBase,
     patch,
@@ -17,18 +25,12 @@
     assert_match,
     fixture_path
 )
-from git import (
-    Git,
-    GitCommandError,
-    GitCommandNotFound,
-    Repo,
-    cmd
-)
 from git.test.lib import with_rw_directory
-
-from git.compat import PY3, is_darwin
 from git.util import finalize_process
 
+import os.path as osp
+
+
 try:
     from unittest import mock
 except ImportError:
@@ -147,7 +149,7 @@ def test_cmd_override(self):
         exc = GitCommandNotFound
         try:
             # set it to something that doens't exist, assure it raises
-            type(self.git).GIT_PYTHON_GIT_EXECUTABLE = os.path.join(
+            type(self.git).GIT_PYTHON_GIT_EXECUTABLE = osp.join(
                 "some", "path", "which", "doesn't", "exist", "gitbinary")
             self.failUnlessRaises(exc, self.git.version)
         finally:
@@ -198,13 +200,13 @@ def test_environment(self, rw_dir):
         self.assertEqual(new_env, {'VARKEY': 'VARVALUE'})
         self.assertEqual(self.git.environment(), {})
 
-        path = os.path.join(rw_dir, 'failing-script.sh')
+        path = osp.join(rw_dir, 'failing-script.sh')
         with open(path, 'wt') as stream:
             stream.write("#!/usr/bin/env sh\n"
                          "echo FOO\n")
         os.chmod(path, 0o777)
 
-        rw_repo = Repo.init(os.path.join(rw_dir, 'repo'))
+        rw_repo = Repo.init(osp.join(rw_dir, 'repo'))
         remote = rw_repo.create_remote('ssh-origin', "ssh://git@server/foo")
 
         with rw_repo.git.custom_environment(GIT_SSH=path):
diff --git a/git/test/test_index.py b/git/test/test_index.py
index d851743ef..0fdc120cd 100644
--- a/git/test/test_index.py
+++ b/git/test/test_index.py
@@ -43,12 +43,14 @@
     fixture,
     with_rw_repo
 )
-from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.test.lib import with_rw_directory
 from git.util import Actor, rmtree
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from gitdb.base import IStream
 from gitdb.util import hex_to_bin
 
+import os.path as osp
+
 
 class TestIndex(TestBase):
 
@@ -85,7 +87,7 @@ def _reset_progress(self):
     def _assert_entries(self, entries):
         for entry in entries:
             assert isinstance(entry, BaseIndexEntry)
-            assert not os.path.isabs(entry.path)
+            assert not osp.isabs(entry.path)
             assert "\\" not in entry.path
         # END for each entry
 
@@ -329,7 +331,7 @@ def test_index_file_diffing(self, rw_repo):
 
         # reset the working copy as well to current head,to pull 'back' as well
         new_data = b"will be reverted"
-        file_path = os.path.join(rw_repo.working_tree_dir, "CHANGES")
+        file_path = osp.join(rw_repo.working_tree_dir, "CHANGES")
         with open(file_path, "wb") as fp:
             fp.write(new_data)
         index.reset(rev_head_parent, working_tree=True)
@@ -340,26 +342,26 @@ def test_index_file_diffing(self, rw_repo):
             assert fp.read() != new_data
 
         # test full checkout
-        test_file = os.path.join(rw_repo.working_tree_dir, "CHANGES")
+        test_file = osp.join(rw_repo.working_tree_dir, "CHANGES")
         with open(test_file, 'ab') as fd:
             fd.write(b"some data")
         rval = index.checkout(None, force=True, fprogress=self._fprogress)
         assert 'CHANGES' in list(rval)
         self._assert_fprogress([None])
-        assert os.path.isfile(test_file)
+        assert osp.isfile(test_file)
 
         os.remove(test_file)
         rval = index.checkout(None, force=False, fprogress=self._fprogress)
         assert 'CHANGES' in list(rval)
         self._assert_fprogress([None])
-        assert os.path.isfile(test_file)
+        assert osp.isfile(test_file)
 
         # individual file
         os.remove(test_file)
         rval = index.checkout(test_file, fprogress=self._fprogress)
         self.assertEqual(list(rval)[0], 'CHANGES')
         self._assert_fprogress([test_file])
-        assert os.path.exists(test_file)
+        assert osp.exists(test_file)
 
         # checking out non-existing file throws
         self.failUnlessRaises(CheckoutError, index.checkout, "doesnt_exist_ever.txt.that")
@@ -373,7 +375,7 @@ def test_index_file_diffing(self, rw_repo):
             index.checkout(test_file)
         except CheckoutError as e:
             self.assertEqual(len(e.failed_files), 1)
-            self.assertEqual(e.failed_files[0], os.path.basename(test_file))
+            self.assertEqual(e.failed_files[0], osp.basename(test_file))
             self.assertEqual(len(e.failed_files), len(e.failed_reasons))
             self.assertIsInstance(e.failed_reasons[0], string_types)
             self.assertEqual(len(e.valid_files), 0)
@@ -388,7 +390,7 @@ def test_index_file_diffing(self, rw_repo):
         assert not open(test_file, 'rb').read().endswith(append_data)
 
         # checkout directory
-        rmtree(os.path.join(rw_repo.working_tree_dir, "lib"))
+        rmtree(osp.join(rw_repo.working_tree_dir, "lib"))
         rval = index.checkout('lib')
         assert len(list(rval)) > 1
 
@@ -399,7 +401,7 @@ def _count_existing(self, repo, files):
         existing = 0
         basedir = repo.working_tree_dir
         for f in files:
-            existing += os.path.isfile(os.path.join(basedir, f))
+            existing += osp.isfile(osp.join(basedir, f))
         # END for each deleted file
         return existing
     # END num existing helper
@@ -458,7 +460,7 @@ def mixed_iterator():
         self.failUnlessRaises(TypeError, index.remove, [1])
 
         # absolute path
-        deleted_files = index.remove([os.path.join(rw_repo.working_tree_dir, "lib")], r=True)
+        deleted_files = index.remove([osp.join(rw_repo.working_tree_dir, "lib")], r=True)
         assert len(deleted_files) > 1
         self.failUnlessRaises(ValueError, index.remove, ["/doesnt/exists"])
 
@@ -525,9 +527,9 @@ def mixed_iterator():
         # re-add all files in lib
         # get the lib folder back on disk, but get an index without it
         index.reset(new_commit.parents[0], working_tree=True).reset(new_commit, working_tree=False)
-        lib_file_path = os.path.join("lib", "git", "__init__.py")
+        lib_file_path = osp.join("lib", "git", "__init__.py")
         assert (lib_file_path, 0) not in index.entries
-        assert os.path.isfile(os.path.join(rw_repo.working_tree_dir, lib_file_path))
+        assert osp.isfile(osp.join(rw_repo.working_tree_dir, lib_file_path))
 
         # directory
         entries = index.add(['lib'], fprogress=self._fprogress_add)
@@ -536,14 +538,14 @@ def mixed_iterator():
         assert len(entries) > 1
 
         # glob
-        entries = index.reset(new_commit).add([os.path.join('lib', 'git', '*.py')], fprogress=self._fprogress_add)
+        entries = index.reset(new_commit).add([osp.join('lib', 'git', '*.py')], fprogress=self._fprogress_add)
         self._assert_entries(entries)
         self._assert_fprogress(entries)
         self.assertEqual(len(entries), 14)
 
         # same file
         entries = index.reset(new_commit).add(
-            [os.path.join(rw_repo.working_tree_dir, 'lib', 'git', 'head.py')] * 2, fprogress=self._fprogress_add)
+            [osp.join(rw_repo.working_tree_dir, 'lib', 'git', 'head.py')] * 2, fprogress=self._fprogress_add)
         self._assert_entries(entries)
         self.assertEqual(entries[0].mode & 0o644, 0o644)
         # would fail, test is too primitive to handle this case
@@ -583,7 +585,7 @@ def mixed_iterator():
             for target in ('/etc/nonexisting', '/etc/passwd', '/etc'):
                 basename = "my_real_symlink"
 
-                link_file = os.path.join(rw_repo.working_tree_dir, basename)
+                link_file = osp.join(rw_repo.working_tree_dir, basename)
                 os.symlink(target, link_file)
                 entries = index.reset(new_commit).add([link_file], fprogress=self._fprogress_add)
                 self._assert_entries(entries)
@@ -645,7 +647,7 @@ def mixed_iterator():
         # TEST RENAMING
         def assert_mv_rval(rval):
             for source, dest in rval:
-                assert not os.path.exists(source) and os.path.exists(dest)
+                assert not osp.exists(source) and osp.exists(dest)
             # END for each renamed item
         # END move assertion utility
 
@@ -661,7 +663,7 @@ def assert_mv_rval(rval):
         paths = ['LICENSE', 'VERSION', 'doc']
         rval = index.move(paths, dry_run=True)
         self.assertEqual(len(rval), 2)
-        assert os.path.exists(paths[0])
+        assert osp.exists(paths[0])
 
         # again, no dry run
         rval = index.move(paths)
@@ -719,8 +721,8 @@ def make_paths():
         index.add(files, write=True)
         if is_win:
             hp = hook_path('pre-commit', index.repo.git_dir)
-            hpd = os.path.dirname(hp)
-            if not os.path.isdir(hpd):
+            hpd = osp.dirname(hp)
+            if not osp.isdir(hpd):
                 os.mkdir(hpd)
             with open(hp, "wt") as fp:
                 fp.write("#!/usr/bin/env sh\necho stdout; echo stderr 1>&2; exit 1")
@@ -766,7 +768,7 @@ def make_paths():
         for fkey in keys:
             assert fkey in index.entries
         for absfile in absfiles:
-            assert os.path.isfile(absfile)
+            assert osp.isfile(absfile)
 
     @with_rw_repo('HEAD')
     def test_compare_write_tree(self, rw_repo):
@@ -815,7 +817,7 @@ def test_index_bare_add(self, rw_bare_repo):
 
         # Adding using a path should still require a non-bare repository.
         asserted = False
-        path = os.path.join('git', 'test', 'test_index.py')
+        path = osp.join('git', 'test', 'test_index.py')
         try:
             rw_bare_repo.index.add([path])
         except InvalidGitRepositoryError:
@@ -829,7 +831,7 @@ def test_index_bare_add(self, rw_bare_repo):
     @with_rw_directory
     def test_add_utf8P_path(self, rw_dir):
         # NOTE: fp is not a Unicode object in python 2 (which is the source of the problem)
-        fp = os.path.join(rw_dir, 'ø.txt')
+        fp = osp.join(rw_dir, 'ø.txt')
         with open(fp, 'wb') as fs:
             fs.write(u'content of ø'.encode('utf-8'))
 
@@ -840,7 +842,7 @@ def test_add_utf8P_path(self, rw_dir):
     @with_rw_directory
     def test_add_a_file_with_wildcard_chars(self, rw_dir):
         # see issue #407
-        fp = os.path.join(rw_dir, '[.exe')
+        fp = osp.join(rw_dir, '[.exe')
         with open(fp, "wb") as f:
             f.write(b'something')
 
diff --git a/git/test/test_reflog.py b/git/test/test_reflog.py
index dffedf3b6..e43a1dc0c 100644
--- a/git/test/test_reflog.py
+++ b/git/test/test_reflog.py
@@ -1,17 +1,19 @@
-from git.test.lib import (
-    TestBase,
-    fixture_path
-)
+import os
+import tempfile
+
 from git.objects import IndexObject
 from git.refs import (
     RefLogEntry,
     RefLog
 )
+from git.test.lib import (
+    TestBase,
+    fixture_path
+)
 from git.util import Actor, rmtree
 from gitdb.util import hex_to_bin
 
-import tempfile
-import os
+import os.path as osp
 
 
 class TestRefLog(TestBase):
@@ -42,7 +44,7 @@ def test_base(self):
         os.mkdir(tdir)
 
         rlp_master_ro = RefLog.path(self.rorepo.head)
-        assert os.path.isfile(rlp_master_ro)
+        assert osp.isfile(rlp_master_ro)
 
         # simple read
         reflog = RefLog.from_file(rlp_master_ro)
@@ -70,7 +72,7 @@ def test_base(self):
         cr = self.rorepo.config_reader()
         for rlp in (rlp_head, rlp_master):
             reflog = RefLog.from_file(rlp)
-            tfile = os.path.join(tdir, os.path.basename(rlp))
+            tfile = osp.join(tdir, osp.basename(rlp))
             reflog.to_file(tfile)
             assert reflog.write() is reflog
 
diff --git a/git/test/test_refs.py b/git/test/test_refs.py
index 43f1dcc72..fd0be1080 100644
--- a/git/test/test_refs.py
+++ b/git/test/test_refs.py
@@ -4,10 +4,8 @@
 # This module is part of GitPython and is released under
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
 
-from git.test.lib import (
-    TestBase,
-    with_rw_repo
-)
+from itertools import chain
+
 from git import (
     Reference,
     Head,
@@ -18,11 +16,15 @@
     GitCommandError,
     RefLog
 )
-import git.refs as refs
-from git.util import Actor
 from git.objects.tag import TagObject
-from itertools import chain
-import os
+from git.test.lib import (
+    TestBase,
+    with_rw_repo
+)
+from git.util import Actor
+
+import git.refs as refs
+import os.path as osp
 
 
 class TestRefs(TestBase):
@@ -268,10 +270,10 @@ def test_head_reset(self, rw_repo):
             assert tmp_head == new_head and tmp_head.object == new_head.object
 
             logfile = RefLog.path(tmp_head)
-            assert os.path.isfile(logfile)
+            assert osp.isfile(logfile)
             Head.delete(rw_repo, tmp_head)
             # deletion removes the log as well
-            assert not os.path.isfile(logfile)
+            assert not osp.isfile(logfile)
             heads = rw_repo.heads
             assert tmp_head not in heads and new_head not in heads
             # force on deletion testing would be missing here, code looks okay though ;)
@@ -450,12 +452,12 @@ def test_head_reset(self, rw_repo):
         symbol_ref_path = "refs/symbol_ref"
         symref = SymbolicReference(rw_repo, symbol_ref_path)
         assert symref.path == symbol_ref_path
-        symbol_ref_abspath = os.path.join(rw_repo.git_dir, symref.path)
+        symbol_ref_abspath = osp.join(rw_repo.git_dir, symref.path)
 
         # set it
         symref.reference = new_head
         assert symref.reference == new_head
-        assert os.path.isfile(symbol_ref_abspath)
+        assert osp.isfile(symbol_ref_abspath)
         assert symref.commit == new_head.commit
 
         for name in ('absname', 'folder/rela_name'):
@@ -507,7 +509,7 @@ def test_head_reset(self, rw_repo):
         rw_repo.head.reference = Head.create(rw_repo, "master")
 
         # At least the head should still exist
-        assert os.path.isfile(os.path.join(rw_repo.git_dir, 'HEAD'))
+        assert osp.isfile(osp.join(rw_repo.git_dir, 'HEAD'))
         refs = list(SymbolicReference.iter_items(rw_repo))
         assert len(refs) == 1
 
diff --git a/git/test/test_repo.py b/git/test/test_repo.py
index 314201eaa..4b21db4b9 100644
--- a/git/test/test_repo.py
+++ b/git/test/test_repo.py
@@ -203,8 +203,8 @@ def test_init(self):
         prev_cwd = os.getcwd()
         os.chdir(tempfile.gettempdir())
         git_dir_rela = "repos/foo/bar.git"
-        del_dir_abs = os.path.abspath("repos")
-        git_dir_abs = os.path.abspath(git_dir_rela)
+        del_dir_abs = osp.abspath("repos")
+        git_dir_abs = osp.abspath(git_dir_rela)
         try:
             # with specific path
             for path in (git_dir_rela, git_dir_abs):
@@ -212,7 +212,7 @@ def test_init(self):
                 self.assertIsInstance(r, Repo)
                 assert r.bare is True
                 assert not r.has_separate_working_tree()
-                assert os.path.isdir(r.git_dir)
+                assert osp.isdir(r.git_dir)
 
                 self._assert_empty_repo(r)
 
@@ -306,16 +306,16 @@ def test_is_dirty(self):
     def test_is_dirty_with_path(self, rwrepo):
         assert rwrepo.is_dirty(path="git") is False
 
-        with open(os.path.join(rwrepo.working_dir, "git", "util.py"), "at") as f:
+        with open(osp.join(rwrepo.working_dir, "git", "util.py"), "at") as f:
             f.write("junk")
         assert rwrepo.is_dirty(path="git") is True
         assert rwrepo.is_dirty(path="doc") is False
 
-        rwrepo.git.add(os.path.join("git", "util.py"))
+        rwrepo.git.add(osp.join("git", "util.py"))
         assert rwrepo.is_dirty(index=False, path="git") is False
         assert rwrepo.is_dirty(path="git") is True
 
-        with open(os.path.join(rwrepo.working_dir, "doc", "no-such-file.txt"), "wt") as f:
+        with open(osp.join(rwrepo.working_dir, "doc", "no-such-file.txt"), "wt") as f:
             f.write("junk")
         assert rwrepo.is_dirty(path="doc") is False
         assert rwrepo.is_dirty(untracked_files=True, path="doc") is True
@@ -494,10 +494,10 @@ def test_tilde_and_env_vars_in_repo_path(self, rw_dir):
         ph = os.environ.get('HOME')
         try:
             os.environ['HOME'] = rw_dir
-            Repo.init(os.path.join('~', 'test.git'), bare=True)
+            Repo.init(osp.join('~', 'test.git'), bare=True)
 
             os.environ['FOO'] = rw_dir
-            Repo.init(os.path.join('$FOO', 'test.git'), bare=True)
+            Repo.init(osp.join('$FOO', 'test.git'), bare=True)
         finally:
             if ph:
                 os.environ['HOME'] = ph
@@ -785,7 +785,7 @@ def test_submodule_update(self, rwrepo):
     @with_rw_repo('HEAD')
     def test_git_file(self, rwrepo):
         # Move the .git directory to another location and create the .git file.
-        real_path_abs = os.path.abspath(join_path_native(rwrepo.working_tree_dir, '.real'))
+        real_path_abs = osp.abspath(join_path_native(rwrepo.working_tree_dir, '.real'))
         os.rename(rwrepo.git_dir, real_path_abs)
         git_file_path = join_path_native(rwrepo.working_tree_dir, '.git')
         with open(git_file_path, 'wb') as fp:
@@ -793,13 +793,13 @@ def test_git_file(self, rwrepo):
 
         # Create a repo and make sure it's pointing to the relocated .git directory.
         git_file_repo = Repo(rwrepo.working_tree_dir)
-        self.assertEqual(os.path.abspath(git_file_repo.git_dir), real_path_abs)
+        self.assertEqual(osp.abspath(git_file_repo.git_dir), real_path_abs)
 
         # Test using an absolute gitdir path in the .git file.
         with open(git_file_path, 'wb') as fp:
             fp.write(('gitdir: %s\n' % real_path_abs).encode('ascii'))
         git_file_repo = Repo(rwrepo.working_tree_dir)
-        self.assertEqual(os.path.abspath(git_file_repo.git_dir), real_path_abs)
+        self.assertEqual(osp.abspath(git_file_repo.git_dir), real_path_abs)
 
     @skipIf(HIDE_WINDOWS_KNOWN_ERRORS and PY3,
             "FIXME: smmp fails with: TypeError: Can't convert 'bytes' object to str implicitly")
@@ -840,7 +840,7 @@ def test_empty_repo(self, rw_dir):
         # It's expected to not be able to access a tree
         self.failUnlessRaises(ValueError, r.tree)
 
-        new_file_path = os.path.join(rw_dir, "new_file.ext")
+        new_file_path = osp.join(rw_dir, "new_file.ext")
         touch(new_file_path)
         r.index.add([new_file_path])
         r.index.commit("initial commit\nBAD MESSAGE 1\n")
diff --git a/git/test/test_tree.py b/git/test/test_tree.py
index f36c43378..f92598743 100644
--- a/git/test/test_tree.py
+++ b/git/test/test_tree.py
@@ -5,7 +5,6 @@
 # the BSD License: http://www.opensource.org/licenses/bsd-license.php
 
 from io import BytesIO
-import os
 import sys
 from unittest.case import skipIf
 
@@ -13,8 +12,10 @@
     Tree,
     Blob
 )
-from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.test.lib import TestBase
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
+
+import os.path as osp
 
 
 class TestTree(TestBase):
@@ -90,12 +91,12 @@ def test_traverse(self):
         assert len(set(b for b in root if isinstance(b, Blob)) | set(root.blobs)) == len(root.blobs)
         subitem = trees[0][0]
         assert "/" in subitem.path
-        assert subitem.name == os.path.basename(subitem.path)
+        assert subitem.name == osp.basename(subitem.path)
 
         # assure that at some point the traversed paths have a slash in them
         found_slash = False
         for item in root.traverse():
-            assert os.path.isabs(item.abspath)
+            assert osp.isabs(item.abspath)
             if '/' in item.path:
                 found_slash = True
             # END check for slash
diff --git a/git/util.py b/git/util.py
index 992937fb5..9658baa96 100644
--- a/git/util.py
+++ b/git/util.py
@@ -128,7 +128,7 @@ def stream_copy(source, destination, chunk_size=512 * 1024):
 
 
 def join_path(a, *p):
-    """Join path tokens together similar to os.path.join, but always use
+    """Join path tokens together similar to osp.join, but always use
     '/' instead of possibly '\' on windows."""
     path = a
     for b in p:
@@ -206,7 +206,7 @@ def is_exec(fpath):
     progs = []
     if not path:
         path = os.environ["PATH"]
-    for folder in path.split(osp.pathsep):
+    for folder in path.split(os.pathsep):
         folder = folder.strip('"')
         if folder:
             exe_path = osp.join(folder, program)
@@ -222,7 +222,7 @@ def _cygexpath(drive, path):
         #  It's an error, leave it alone just slashes)
         p = path
     else:
-        p = path and osp.normpath(osp.expandvars(os.path.expanduser(path)))
+        p = path and osp.normpath(osp.expandvars(osp.expanduser(path)))
         if osp.isabs(p):
             if drive:
                 # Confusing, maybe a remote system should expand vars.