code: def serialize(self, x):
      params = bz2.compress(
          json.dumps(x.to_str_params(only_significant=True)).encode()
      ).hex()
      values = dict(type=x.get_task_family(), params=params)
      return luigi.DictParameter().serialize(values)
  
imports: import bz2
  import json
  from logging import getLogger
  import luigi
  from luigi import task_register
  import gokart
label_desc: Use image node_id 5 for calling the TaskInstanceParameter obj's underlying member method code with example usage: obj.serialize(x) and returns: luigi