[question] TypeError: 'NoneType' object is not callable with user defined env

[Charles-Lim93]

Hello. I'm using Stable-baseline3 for Reinforcement Learning in Airsim environment. My gym and stable-baseline3 code works well when I do learning.

But, it creates error = TypeError: 'NoneType' object is not callable

when I load the network to evalulate the network that I trained.

Phenomenon are describe below; 1. Training works fine, and successful to create .zip file that contatins network information

2. But when load model.load standalone, then it gets error "model = DQN.load("dqn_airsim_drone_policy", env = env)"

3. Interesting thing is that when I use evaluate_policy function, then it iterates for n_eval_episodes that set, then get same error on 2.

"model = DQN.load("dqn_airsim_drone_policy", env = env) mean_reward, std_reward = evaluate_policy(model, model.get_env(), n_eval_episodes=10)"

Before begin first here's my code:

`import setup_path import gym import airgym import time

from stable_baselines3 import DQN from stable_baselines3.common.monitor import Monitor from stable_baselines3.common.vec_env import DummyVecEnv, VecTransposeImage from stable_baselines3.common.evaluation import evaluate_policy from stable_baselines3.common.callbacks import EvalCallback

'# Create a DummyVecEnv for main airsim gym env' env = DummyVecEnv( [ lambda: Monitor( gym.make( "airgym:airsim-drone-sample-v0", ip_address="127.0.0.1", step_length = 0.1, image_shape=(84, 84, 1), ) ) ] )

env = VecTransposeImage(env)

'# Train the agent => works and create .zip file' model.learn( total_timesteps=1e5, tb_log_name="dqn_airsim_dronerun" + str(time.time()), **kwargs )

'# Load the trained agent => TypeError' model = DQN.load("dqn_airsim_drone_policy", env = env)

'# evaluate policy => Type Error' mean_reward, std_reward = evaluate_policy(model, model.get_env(), n_eval_episodes=10)

my full error is ' Exception ignored in: <function AirSimDroneEnv.del at 0x000001E8977C3D38> Traceback (most recent call last): File "c:\Users\user\source\repos\AirSim\PythonClient\reinforcement_learning\airgym\envs\drone_env.py", line 57, in del File "c:\Users\user\source\repos\AirSim\PythonClient\airsim\client.py", line 26, in reset File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\msgpackrpc\session.py", line 41, in call File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\msgpackrpc\future.py", line 25, in get File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\msgpackrpc\future.py", line 22, in join File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\msgpackrpc\loop.py", line 22, in start File "C:\Users\user\AppData\Local\Programs\Python\Python37\lib\site-packages\tornado\ioloop.py", line 711, in start TypeError: 'NoneType' object is not callable '

System Info

• GPU models and configuration = CPU i5, GPU RTX 2080 Ti
• Python version == 3.7
• Tensorflow version == 1

Thank you in advanced, Best