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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 downvote(self):
 """ Dislike this. A downvote will replace a neutral vote or an upvote. Downvoting something the authenticated user has already downvoted will set the vote to neutral. """

        url = self._imgur._base_url + "/3/gallery/{0}/vote/down".format(self.id)
        return self._imgur._send_request(url, needs_auth=True, method='POST')