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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 disconnect(self, sid, namespace):
 """Register a client disconnect from a namespace."""

        if namespace not in self.rooms:
            return
        rooms = []
        for room_name, room in six.iteritems(self.rooms[namespace].copy()):
            if sid in room:
                rooms.append(room_name)
        for room in rooms:
            self.leave_room(sid, namespace, room)
        if sid in self.callbacks and namespace in self.callbacks[sid]:
            del self.callbacks[sid][namespace]
            if len(self.callbacks[sid]) == 0:
                del self.callbacks[sid]
        if namespace in self.pending_disconnect and \
                sid in self.pending_disconnect[namespace]:
            self.pending_disconnect[namespace].remove(sid)
            if len(self.pending_disconnect[namespace]) == 0:
                del self.pending_disconnect[namespace]