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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def _dump_message_field(self, writer, msg, field, fvalue=None):
 """ Dumps a message field to the writer. Field is defined by the message field specification. :param writer: :param msg: :param field: :param fvalue: :return: """

        fname, ftype, params = field[0], field[1], field[2:]
        fvalue = getattr(msg, fname, None) if fvalue is None else fvalue
        await self.dump_field(writer, fvalue, ftype, params)