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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 _shutdown_multicast_socket(self):
 """ Shutdown multicast socket :rtype: None """

        self.debug("()")
        self._drop_membership_multicast_socket()
        self._listening.remove(self._multicast_socket)
        self._multicast_socket.close()
        self._multicast_socket = None