def train(params):

    # create model
    env = FlattenObservation(gym.make(params.get("environment")))
    exp_name = params.get("model_name") + "_train_" + params.get("environment")
    log_dir = './logs/' + exp_name
    expert_name = 'expert_{0}'.format(exp_name)

    if params.get("model_name") == 'TRPO':
        print("Loading TRPO Model")
        model = TRPO(MlpPolicy, env, verbose=1, tensorboard_log=log_dir)
        model.learn(total_timesteps=params.get("train_steps"))
        model.save(exp_name)

    if params.get("model_name") == 'PPO':
        print("Loading PPO Model")
        model = PPO1(MlpPolicy,
                     env,
                     verbose=1,
                     tensorboard_log=log_dir,
                     entcoeff=params.get("ent_coef"),
                     gamma=params.get("gamma"),
                     optim_batchsize=params.get("batch_size"),
                     clip_param=params.get("clip_range"),
                     lam=params.get("gae_lambda"))
        model.learn(total_timesteps=params.get("train_steps"))
        model.save(exp_name)

    if params.get("expert_exists") is False:
        print("Training expert trajectories")
        # Train expert controller (if needed) and record expert trajectories.
        generate_expert_traj(model,
                             expert_name,
                             n_timesteps=params.get("expert_timesteps"),
                             n_episodes=params.get("n_episodes"))

    dataset = ExpertDataset(
        expert_path='{0}.npz'.format(expert_name),
        traj_limitation=-1,
        randomize=True,  # if the dataset should be shuffled
        verbose=1)

    model = GAIL('MlpPolicy', env, dataset, verbose=1,
                 tensorboard_log=log_dir)  # Check out for defaults

    if params.get("pre_train") is True:
        print("Pretraining Dataset with Behavioural Cloning")
        model.pretrain(dataset, n_epochs=10000)

    print("Executing GAIL Learning")
    model.learn(total_timesteps=params.get("train_steps"))
    model.save("BC" + exp_name)

    env.close()
    del env
    # make_vec_env() is used for multiprocess enviroment
    env = make_vec_env('gym_quadruped:quadruped-v0', n_envs=4)

    check_dir('./pretrain/PPO/')
    model = PPO2(MlpPolicy, env, verbose=1, tensorboard_log='./pretrain/PPO/')

else:
    print('Model choosen not available, check spelling or if it is supported')

# Using only one expert trajectory
# you can specify `traj_limitation=-1` for using the whole dataset
dataset = ExpertDataset(expert_path='./pretrain/dummy_quadruped.npz',
                        traj_limitation=-1,
                        batch_size=128)

model.pretrain(dataset, n_epochs=args['pt'])

if args['pretrainVisualization']:
    # Test the pre-trained model
    env = model.get_env()
    obs = env.reset()

    reward_sum = 0.0
    for _ in range(1000):
        action, _ = model.predict(obs)
        obs, reward, done, _ = env.step(action)
        reward_sum += reward
        env.render()
        if done:
            print(reward_sum)
            reward_sum = 0.0