def start(self, context: Context):
        """Start runner

        Args:
            context: shared in runner. Don't write data to context in this
            method. Only can read data via `context.data`.
        """
Start runner

        Args:
            context: shared in runner. Don't write data to context in this
            method. Only can read data via `context.data`.
        
web_console_v2/api/fedlearner_webconsole/composer/interface.py