code: def merge_envs(*args):
      
      env = {}
      for arg in args:
          if not arg:
              continue
          env.update(arg)
      return env
docs: Union of one or more dictionaries.
  
      In case of duplicate keys, the values in the right-most arguments will
      squash (overwrite) the value provided by any dict preceding it.
  
      :param args: Sequence of ``dict`` objects that should be merged.
      :return: A ``dict`` containing the union of keys in all input dicts.