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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 migrate_repo(self, auth, clone_addr, uid, repo_name, auth_username=None, auth_password=None, mirror=False, private=False, description=None):
 """ Migrate a repository from another Git hosting source for the authenticated user. :param auth.Authentication auth: authentication object :param str clone_addr: Remote Git address (HTTP/HTTPS URL or local path) :param int uid: user ID of repository owner :param str repo_name: Repository name :param bool mirror: Repository will be a mirror. Default is false :param bool private: Repository will be private. Default is false :param str description: Repository description :return: a representation of the migrated repository :rtype: GogsRepo :raises NetworkFailure: if there is an error communicating with the server :raises ApiFailure: if the request cannot be serviced """

        # "auth_username": auth_username,
        # "auth_password": auth_password,

        data = {
            "clone_addr": clone_addr,
            "uid": uid,
            "repo_name": repo_name,
            "mirror": mirror,
            "private": private,
            "description": description,
        }
        data = {k: v for (k, v) in data.items() if v is not None}
        url = "/repos/migrate"
        response = self.post(url, auth=auth, data=data)
        return GogsRepo.from_json(response.json())