Returns the value of the argument with the given name.

        If default is not provided, the argument is considered to be
        required, and we raise a `MissingArgumentError` if it is missing.

        If the argument appears in the request more than once, we return the
        last value.

        This method searches both the query and body arguments.

def get_argument(  # noqa: F811
        self,
        name: str,
        default: Union[None, str, _ArgDefaultMarker] = _ARG_DEFAULT,
        strip: bool = True,
    ) -> Optional[str]:
        """Returns the value of the argument with the given name.

        If default is not provided, the argument is considered to be
        required, and we raise a `MissingArgumentError` if it is missing.

        If the argument appears in the request more than once, we return the
        last value.

        This method searches both the query and body arguments.
        """
        return self._get_argument(name, default, self.request.arguments, strip)