code: def body_to_json(self):
      return {
          self._ACTION_ID_JSON_KEY: self.action_id,
          self._ACTION_INVOCATION_ID_JSON_KEY: self.action_invocation_id,
          self._ARGUMENT_JSON_KEY: self.argument,
      }
  
imports: from neptune.attributes.constants import SIGNAL_TYPE_ABORT, SIGNAL_TYPE_STOP
label_desc: Use image node_id 4 for calling the ActionInvocationMessage obj's underlying member method code with example usage: obj.body_to_json() and returns: dict