Fix minor issue in gym_wrapper (#628)

* Fix minor issue in gym_wrapper

* fix

metadrive/envs/gym_wrapper.py

@@ -6,6 +6,11 @@
     import gym.spaces
 
     def gymnasiumToGym(space: gymnasium.spaces.Space) -> gym.spaces.Space:
+        return gymnasium_to_gym(space)
+
+    def gymnasium_to_gym(space: gymnasium.spaces.Space) -> gym.spaces.Space:
+        if isinstance(space, gym.spaces.Space):
+            return space
         if isinstance(space, gymnasium.spaces.Box):
             return gym.spaces.Box(low=space.low, high=space.high, shape=space.shape)
         elif isinstance(space, gymnasium.spaces.Discrete):
@@ -17,9 +22,14 @@ def gymnasiumToGym(space: gymnasium.spaces.Space) -> gym.spaces.Space:
         elif isinstance(space, gymnasium.spaces.Dict):
             return gym.spaces.Dict({key: gymnasiumToGym(subspace) for key, subspace in space.spaces.items()})
         else:
-            raise ValueError("unsupported space")
+            raise ValueError(f"unsupported space: {type(space)}!")
 
     def gymToGymnasium(space: gym.spaces.Space) -> gymnasium.spaces.Space:
+        return gym_to_gymnasium(space)
+
+    def gym_to_gymnasium(space: gym.spaces.Space) -> gymnasium.spaces.Space:
+        if isinstance(space, gymnasium.spaces.Space):
+            return space
         if isinstance(space, gym.spaces.Box):
             return gymnasium.spaces.Box(low=space.low, high=space.high, shape=space.shape)
         elif isinstance(space, gym.spaces.Discrete):
@@ -31,9 +41,12 @@ def gymToGymnasium(space: gym.spaces.Space) -> gymnasium.spaces.Space:
         elif isinstance(space, gym.spaces.Dict):
             return gymnasium.spaces.Dict({key: gymToGymnasium(subspace) for key, subspace in space.spaces.items()})
         else:
-            raise ValueError("unsupported space")
+            raise ValueError(f"unsupported space: {type(space)}!")
 
     def createGymWrapper(inner_class: type):
+        return create_gym_wrapper(inner_class)
+
+    def create_gym_wrapper(inner_class: type):
         """
         "inner_class": A gymnasium based Metadrive environment class
         """