diff --git a/src/pep8ext_naming.py b/src/pep8ext_naming.py
index 676805d..7abf0dd 100644
--- a/src/pep8ext_naming.py
+++ b/src/pep8ext_naming.py
@@ -1,5 +1,7 @@
 """Checker of PEP-8 Naming Conventions."""
+import ast
 import sys
+from ast import iter_child_nodes
 from collections import deque
 from fnmatch import fnmatch
 from functools import partial
@@ -7,12 +9,6 @@
 
 from flake8 import style_guide
 
-try:
-    import ast
-    from ast import iter_child_nodes
-except ImportError:
-    from flake8.util import ast, iter_child_nodes
-
 __version__ = '0.13.1'
 
 PYTHON_VERSION = sys.version_info[:3]