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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 add_vote(self, issue):
 """Register a vote for the current authenticated user on an issue. :param issue: ID or key of the issue to vote on :rtype: Response """

        url = self._get_url('issue/' + str(issue) + '/votes')
        return self._session.post(url)