update flake8 plugin version and fix warnings (#3180)

Author: Chris Elion

.pre-commit-config.yaml

@@ -45,7 +45,7 @@ repos:
                 .*_pb2_grpc.py
             )$
         # flake8-tidy-imports is used for banned-modules, not actually tidying
-        additional_dependencies: [flake8-comprehensions==3.1.4, flake8-tidy-imports==3.1.0, flake8-bugbear==20.1.2]
+        additional_dependencies: [flake8-comprehensions==3.1.4, flake8-tidy-imports==4.0.0, flake8-bugbear==20.1.2]
     -   id: trailing-whitespace
         name: trailing-whitespace-markdown
         types: [markdown]

gym-unity/gym_unity/tests/test_gym.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 import numpy as np
 

ml-agents-envs/mlagents_envs/tests/test_envs.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 
 import numpy as np

ml-agents/mlagents/trainers/tests/mock_brain.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import numpy as np
 
 from mlagents.trainers.brain import CameraResolution, BrainParameters

ml-agents/mlagents/trainers/tests/test_agent_processor.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 import mlagents.trainers.tests.mock_brain as mb
 import numpy as np

ml-agents/mlagents/trainers/tests/test_bcmodule.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 import mlagents.trainers.tests.mock_brain as mb
 

ml-agents/mlagents/trainers/tests/test_multigpu.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 
 from mlagents.tf_utils import tf

ml-agents/mlagents/trainers/tests/test_ppo.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 
 import numpy as np

ml-agents/mlagents/trainers/tests/test_reward_signals.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 import yaml
 import os

ml-agents/mlagents/trainers/tests/test_sac.py

@@ -1,4 +1,4 @@
-import unittest.mock as mock
+from unittest import mock
 import pytest
 import yaml