docs: def populate_model(model_or_inst, excludes=None, only=None):
      """
      Call `make_request_parser()` to build a `RequestParser`, use it extract user request data,
        and padding the data into model instance.
      If user passed a model class, instead of model instance, create a new instance use the extracted data.
      """
      inst = model_or_inst if _is_inst(model_or_inst) else model_or_inst()
  
      parser = make_request_parser(model_or_inst, excludes, only, for_populate=True)
      req_args = parser.parse_args()
  
      for key, value in req_args.items():
          setattr(inst, key, value)
  
      return inst