feat: handling missing gym module

examples/gym-random-hunter.py

@@ -3,12 +3,11 @@
 import argparse
 import json
 
-import gym
-from gym import envs
-
 import gym_wumpus
 from gym_wumpus.envs import WumpusEnv
 
+from gym import envs, error, make
+
 
 def run_episode(env: WumpusEnv):
     obs = env.reset()
@@ -39,13 +38,17 @@ def main():
         return
 
     if args.file is not None:
-        env = gym.make('wumpus-custom-v0', desc=json.load(args.file))
+        env = make('wumpus-custom-v0', desc=json.load(args.file))
     else:
         try:
-            env = gym.make(args.id)
-        except:
-            env = gym.make(default_env)
-    run_episode(env)
+            env = make(args.id)
+        except error.Error as e:
+            print('Bad Gym environment {}, using {}. Error is {}'.format(args.id, default_env, e))
+            env = make(default_env)
+    if isinstance(env, WumpusEnv):
+        run_episode(env)
+    else:
+        print('Environment {} is not a Wumpus world.'.format(env))
 
 
 if __name__ == "__main__":

gym_wumpus/__init__.py

-from gym.envs.registration import register
-
-__version__ = "1.0.0"
+try:
+    from gym.envs.registration import register
+except ImportError as e:
+    raise Exception('OpenAI gym not installed, you should install wumpus package with [gym] feature.') from e
 
 
 register(