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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 like(self, photo_id):
 """ Like a photo on behalf of the logged-in user. This requires the 'write_likes' scope. Note: This action is idempotent; sending the POST request to a single photo multiple times has no additional effect. :param photo_id [string]: The photo’s ID. Required. :return: [Photo]: The Unsplash Photo. """

        url = "/photos/%s/like" % photo_id
        result = self._post(url)
        return PhotoModel.parse(result)