code: def to_list_str(value, encode=None):
      
      result = []
      for index, v in enumerate(value):
          if isinstance(v, dict):
              result.append(to_dict_str(v, encode))
              continue
  
          if isinstance(v, list):
              result.append(to_list_str(v, encode))
              continue
  
          if encode:
              result.append(encode(v))
          else:
              result.append(default_encode(v))
  
      return result
docs: recursively convert list content into string
  
      :arg list value: The list that need to be converted.
      :arg function encode: Function used to encode object.