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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 get(self, sid):
 """ Constructs a ChallengeContext :param sid: A string that uniquely identifies this Challenge, or `latest`. :returns: twilio.rest.authy.v1.service.entity.factor.challenge.ChallengeContext :rtype: twilio.rest.authy.v1.service.entity.factor.challenge.ChallengeContext """

        return ChallengeContext(
            self._version,
            service_sid=self._solution['service_sid'],
            identity=self._solution['identity'],
            factor_sid=self._solution['factor_sid'],
            sid=sid,
        )