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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:
 def _pack(self, msg_type, payload):
 """ Packs the given message type and payload. Turns the resulting message into a byte string. """

        pb = payload.encode('utf-8')
        s = struct.pack('=II', len(pb), msg_type.value)
        return self.MAGIC.encode('utf-8') + s + pb