Fix tests

Author: emailweixu

alf/environments/utils.py

@@ -172,8 +172,10 @@ def create_environment(env_name=None,
     """
 
     if env_name is None:
+        # Keep compatibility with the old default env_name
         env_name = 'CartPole-v0'
     if env_load_fn is None:
+        # Keep compatibility with the old default env_name
         from alf.environments import suite_gym
         env_load_fn = suite_gym.load
 

alf/examples/hybrid_rl/hybrid_sac_pendulum.gin

@@ -1,4 +1,3 @@
-
 include 'sac_pendulum.gin'
 
 # Example config for Hybrid RL training.

alf/examples/ppo_bullet_humanoid.gin

@@ -1,3 +1,4 @@
+import alf.environments.suite_gym
 include 'ppo.gin'
 
 # environment config

alf/examples/sac_pendulum.gin

@@ -1,4 +1,4 @@
-
+import alf.environments.suite_gym
 include 'sac.gin'
 
 import alf.utils.math_ops

alf/examples/sarsa_ddpg_pendulum.gin

@@ -1,3 +1,4 @@
+import alf.environments.suite_gym
 include 'sarsa_ddpg.gin'
 
 # environment config

alf/examples/sarsa_sac_pendulum.gin

@@ -1,3 +1,4 @@
+import alf.environments.suite_gym
 include 'sarsa_sac.gin'
 
 # environment config