class_docstr: An abstract asynchronous, vectorized environment.
  
  :param num_envs: (int) the number of environments
  :param observation_space: (Gym Space) the observation space
  :param action_space: (Gym Space) the action space
docstr: Convert a flexibly-typed reference to environment indices to an implied list of indices.
  
  :param indices: (None,int,Iterable) refers to indices of envs.
  :return: (list) the implied list of indices.
docstr_tok: ["Convert","a","flexibly-typed","reference","to","environment","indices","to","an","implied","list","of","indices",".",":","param","indices",":","(","None",",","int",",","Iterable",")","refers","to","indices","of","envs",".",":","return",":","(","list",")","the","implied","list","of","indices","."]
code: def _get_indices(self, indices):
      """
      Convert a flexibly-typed reference to environment indices to an implied list of indices.
  
      :param indices: (None,int,Iterable) refers to indices of envs.
      :return: (list) the implied list of indices.
      """
      if indices is None:
          indices = range(self.num_envs)
      elif isinstance(indices, int):
          indices = [indices]
      return indices
  
imports: from abc import ABC, abstractmethod
  import inspect
  import pickle
  from typing import Sequence, Optional, List, Union
  import cloudpickle
  import numpy
  from stable_baselines import logger
  from stable_baselines.common.tile_images import tile_images
label_desc: Use image node_id 15 for calling the VecEnv obj's underlying member method code with example usage: obj._get_indices(indices) and returns: indices