class_docstr: Vectorized environment that runs multiple environments in parallel.
  
  It uses ``multiprocessing`` processes, and pipes for communication.
  
  Example::
  
      >>> import gym
      >>> env = gym.vector.AsyncVectorEnv([
      ...     lambda: gym.make("Pendulum-v0", g=9.81),
      ...     lambda: gym.make("Pendulum-v0", g=1.62)
      ... ])
      >>> env.reset()
      array([[-0.8286432 ,  0.5597771 ,  0.90249056],
             [-0.85009176,  0.5266346 ,  0.60007906]], dtype=float32)
class_docstr_tok: ["Vectorized","environment","that","runs","multiple","environments","in","parallel",".","It","uses","``","multiprocessing","``","processes",",","and","pipes","for","communication",".","Example",":",":",">",">",">","import","gym",">",">",">","env","=","gym.vector.AsyncVectorEnv","(","[","...","lambda",":","gym.make","(","``","Pendulum-v0","''",",","g=9.81",")",",","...","lambda",":","gym.make","(","``","Pendulum-v0","''",",","g=1.62",")","...","]",")",">",">",">","env.reset","(",")","array","(","[","[","-0.8286432",",","0.5597771",",","0.90249056","]",",","[","-0.85009176",",","0.5266346",",","0.60007906","]","]",",","dtype=float32",")"]
code: def _assert_is_running(self):
      if self.closed:
          raise ClosedEnvironmentError(
              f"Trying to operate on `{type(self).__name__}`, after a call to `close()`."
          )
  
imports: import multiprocessing
  import sys
  import time
  from copy import deepcopy
  from enum import Enum
  from typing import List, Optional, Sequence, Tuple, Union
  import numpy
  import gym
  from gym import logger
  from gym.core import ObsType
  from gym.error import AlreadyPendingCallError, ClosedEnvironmentError, CustomSpaceError, NoAsyncCallError
  from gym.vector.utils import CloudpickleWrapper, clear_mpi_env_vars, concatenate, create_empty_array, create_shared_memory, iterate, read_from_shared_memory, write_to_shared_memory
  from gym.vector.vector_env import VectorEnv
label_desc: Use image node_id 12 for calling the AsyncVectorEnv obj's underlying member method code with example usage: obj._assert_is_running() without return types