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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 isInRoom(self, _id):
 """ Check a given user is in given room """

        if SockJSRoomHandler._room.has_key(self._gcls() + _id):
            if self in SockJSRoomHandler._room[self._gcls() + _id]:
                return True
        return False