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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 send_notification(self, code, subcode):
 """Utility to send notification message. Closes the socket after sending the message. :Parameters: - `socket`: (socket) - socket over which to send notification message. - `code`: (int) - BGP Notification code - `subcode`: (int) - BGP Notification sub-code RFC ref: http://tools.ietf.org/html/rfc4486 http://www.iana.org/assignments/bgp-parameters/bgp-parameters.xhtml """

        notification = BGPNotification(code, subcode)
        reason = notification.reason
        self._send_with_lock(notification)
        self._signal_bus.bgp_error(self._peer, code, subcode, reason)
        if len(self._localname):
            LOG.error('Sent notification to %r >> %s', self._localname,
                      notification)
        self._socket.close()