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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_deploy_key(self, auth, username, repo_name, title, key_content):
 """ Add a deploy key to the specified repo. :param auth.Authentication auth: authentication object :param str username: username of owner of repository :param str repo_name: the name of the repo :param str title: title of the key to add :param str key_content: content of the key to add :return: a representation of the added deploy key :rtype: GogsRepo.DeployKey :raises NetworkFailure: if there is an error communicating with the server :raises ApiFailure: if the request cannot be serviced """

        data = {
            "title": title,
            "key": key_content
        }
        response = self.post("/repos/{u}/{r}/keys".format(u=username, r=repo_name), auth=auth, data=data)
        return GogsRepo.DeployKey.from_json(response.json())