docs: def create_instance(self, credentials, name, **kwargs):
          """Create an instance based on the configuration data.
          
          TODO: docstring"""
          op_name = create_instance(
              credentials, self.project, self.zone, name,
              machine_type=self.machine_type,
              disk_size_gb=self.disk_size_gb,
              **kwargs)
          
          return op_name