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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 enter_room(self, sid, namespace, room):
 """Add a client to a room."""

        if namespace not in self.rooms:
            self.rooms[namespace] = {}
        if room not in self.rooms[namespace]:
            self.rooms[namespace][room] = {}
        self.rooms[namespace][room][sid] = True