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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_collaborator(self, login):
 """Add ``login`` as a collaborator to a repository. :param str login: (required), login of the user :returns: bool -- True if successful, False otherwise """

        resp = False
        if login:
            url = self._build_url('collaborators', login, base_url=self._api)
            resp = self._boolean(self._put(url), 204, 404)
        return resp