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/diayn_pendulum.gin

@@ -4,7 +4,7 @@ import alf.trainers.policy_trainer
 import alf.algorithms.diayn_algorithm
 import alf.algorithms.goal_generator
 import alf.networks.critic_networks
-
+import alf.environments.suite_gym
 
 # skill related
 num_of_skills=5

alf/examples/hybrid_rl/hybrid_sac_pendulum.gin

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

alf/examples/icm_mountain_car.gin

@@ -2,7 +2,7 @@ import alf.algorithms.agent
 import alf.algorithms.actor_critic_loss
 import alf.algorithms.icm_algorithm
 import alf.algorithms.entropy_target_algorithm
-
+import alf.environments.suite_gym
 
 # environment config
 create_environment.num_parallel_environments=30

alf/examples/mdq_pendulum.gin

@@ -1,7 +1,7 @@
 import alf.utils.math_ops
 import alf.algorithms.agent
 import alf.algorithms.mdq_algorithm
-
+import alf.environments.suite_gym
 
 observation_spec=@get_observation_spec()
 action_spec=@get_action_spec()

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_bipedal_walker.gin

@@ -1,4 +1,5 @@
 include 'sarsa_sac.gin'
+import alf.environments.suite_gym
 
 # Need to install Box2D by "pip install box2d-py"
 create_environment.env_name="BipedalWalker-v2"

alf/examples/sarsa_sac_pendulum.gin

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