diff --git a/src/dipdup/dipdup.py b/src/dipdup/dipdup.py
index 4c576363b..280b26227 100644
--- a/src/dipdup/dipdup.py
+++ b/src/dipdup/dipdup.py
@@ -2,8 +2,8 @@
 import hashlib
 import logging
 from contextlib import suppress
+from os import listdir
 from os.path import join
-from posix import listdir
 from typing import Dict, List, Optional, cast
 
 from apscheduler.schedulers import SchedulerNotRunningError  # type: ignore
diff --git a/src/dipdup/exceptions.py b/src/dipdup/exceptions.py
index da1d7e801..ec1e9f407 100644
--- a/src/dipdup/exceptions.py
+++ b/src/dipdup/exceptions.py
@@ -1,7 +1,7 @@
 import traceback
 from abc import ABC, abstractmethod
-from typing import Optional, Type, Any
 from pprint import pformat
+from typing import Any, Optional, Type
 
 from tabulate import tabulate
 
@@ -144,7 +144,7 @@ def format_help(self) -> str:
 class InvalidDataError(DipDupError):
     """Failed to validate operation/big_map data against a generated type class"""
 
-    def __init__(self, data: Any, type_cls: Type, error_context : Optional[Any] = None) -> None:
+    def __init__(self, data: Any, type_cls: Type, error_context: Optional[Any] = None) -> None:
         super().__init__(None)
         self.data = data
         self.type_name = type_cls.__name__
@@ -154,5 +154,5 @@ def format_help(self) -> str:
         return _data_validation_error.format(
             invalid_data=pformat(self.data, compact=True),
             type_name=self.type_name,
-            error_context=pformat(self.error_context, compact=True)
+            error_context=pformat(self.error_context, compact=True),
         )
diff --git a/src/dipdup/index.py b/src/dipdup/index.py
index 1bdee86ca..9294b4f93 100644
--- a/src/dipdup/index.py
+++ b/src/dipdup/index.py
@@ -3,6 +3,7 @@
 from collections import defaultdict, deque, namedtuple
 from contextlib import suppress
 from typing import Deque, Dict, List, Optional, Set, Tuple, Union, cast
+
 from pydantic.error_wrappers import ValidationError
 
 from dipdup.config import (
@@ -19,9 +20,9 @@
 )
 from dipdup.context import DipDupContext, HandlerContext
 from dipdup.datasources.tzkt.datasource import BigMapFetcher, OperationFetcher, TzktDatasource
+from dipdup.exceptions import InvalidDataError
 from dipdup.models import BigMapData, BigMapDiff, HeadBlockData, OperationData, Origination, State, TemporaryState, Transaction
 from dipdup.utils import FormattedLogger, in_global_transaction
-from dipdup.exceptions import InvalidDataError
 
 # NOTE: Operations of a single contract call
 OperationSubgroup = namedtuple('OperationSubgroup', ('hash', 'counter'))
@@ -300,7 +301,7 @@ async def _on_match(
                     error_context = dict(
                         hash=operation.hash,
                         counter=operation.counter,
-                        nonce=operation.nonce
+                        nonce=operation.nonce,
                     )
                     raise InvalidDataError(operation.parameter_json, parameter_type, error_context) from e