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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 xor(cls, obj, **kwargs):
 """Query an object. :param obj: object to test :param kwargs: query specified in kwargssql :return: `True` if exactly one `kwargs` expression is `True`, `False` otherwise. :rtype: bool """

        return cls.__eval_seqexp(obj, operator.xor, **kwargs)