@classmethod
    def parse_stream_token(cls, string):
        try:
            if string[0] is 's':
                return cls(topological=None, stream=int(string[1:]))
        except:
            pass
        raise SynapseError(400, "Invalid token %r" % (string,))
dataset/ETHPy150Open matrix-org/synapse/synapse/types.py/RoomStreamToken.parse_stream_token/operator `==` -> `is`