Refactoring: bugfix of return type

flatland/envs/observations.py

@@ -640,7 +640,7 @@ class LocalObsForRailEnv(ObservationBuilder):
         direction = np.identity(4)[agent.direction]
         return local_rail_obs, obs_map_state, obs_other_agents_state, direction
 
-    def get_many(self, handles: Optional[List[int]] = None) -> Dict[int, (np.ndarray, np.ndarray, np.ndarray, np.ndarray)]:
+    def get_many(self, handles: Optional[List[int]] = None) -> Dict[int, tuple]:
         """
         Called whenever an observation has to be computed for the `env` environment, for each agent with handle
         in the `handles` list.