Shutdown multicast socket

        :rtype: None

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