def METHOD_NAME(
    self, msg: Union[Exception, str], kwargs: MutableMapping[str, Any]
) -> Tuple[str, MutableMapping[str, Any]]:
    """Process the message to append the prefix.
    Args:
        msg: Message to be prefixed.
        kwargs: Keyword args for the message.
    """
    return self.prefix_template.format(prefix=self.prefix, msg=msg), kwargs