code: def key_file(self):
          
          if self.auth_key:
              key_file_path = os.path.join(orchestration_mkdtemp(), 'key')
              with open(key_file_path, 'w') as fd:
                  fd.write(self.auth_key)
              os.chmod(key_file_path, stat.S_IRUSR)
              return key_file_path
docs: Get the path to the key file containig our auth key, or None.