removing some dependencies

ml-agents-envs/mlagents_envs/gym_wrapper.py

 
 import numpy as np
 
-import gym
+try:
+    import gym
+except ImportError:
+    raise ImportError("gym is not installed, gym required to use the GymToUnityWrapper")
-class GymWrapper(BaseEnv):
+class GymToUnityWrapper(BaseEnv):
     _DEFAULT_BEHAVIOR_NAME = "gym_behavior_name"
     _AGENT_ID = 1
 

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

-from mlagents_envs.gym_wrapper import GymWrapper
+from mlagents_envs.gym_wrapper import GymToUnityWrapper
-import gym
+
+try:
+    import gym
+except ImportError:
+    raise ImportError(
+        "gym is not installed, please call `pip install gym` before running this test"
+    )
-GYM_ENVS = ["CartPole-v1", "MountainCar-v0", "AirRaid-v0"]
+GYM_ENVS = ["CartPole-v1", "MountainCar-v0"]
-    env = GymWrapper(gym.make(name), name)
+    env = GymToUnityWrapper(gym.make(name), name)
     env.close()
 
 
-    env = GymWrapper(gym_env, name)
+    env = GymToUnityWrapper(gym_env, name)
     assert env.get_behavior_names()[0] == name
     if isinstance(gym_env.action_space, gym.spaces.Box):
         assert env.get_behavior_spec(name).action_type == ActionType.CONTINUOUS
 
 @pytest.mark.parametrize("name", GYM_ENVS, ids=GYM_ENVS)
 def test_steps(name):
-    env = GymWrapper(gym.make(name), name)
+    env = GymToUnityWrapper(gym.make(name), name)
     spec = env.get_behavior_spec(name)
     env.reset()
     for _ in range(200):

ml-agents-envs/setup.py

     packages=find_packages(exclude=["*.tests", "*.tests.*", "tests.*", "tests"]),
     zip_safe=False,
     install_requires=[
-        "gym",
-        "cmake",
-        "atari-py",
-        "opencv-python",
-        "gym[atari]",
         "cloudpickle",
         "grpcio>=1.11.0",
         "numpy>=1.14.1,<2.0",