code: def serialize(self):
      parent_ser = super(Counter, self).serialize()
      parent_ser["_count"] = self._count
      return parent_ser
  
imports: import time
  from contextlib import contextmanager
  from metaflow.sidecar import Message, MessageTypes, Sidecar
label_desc: Use image node_id 5 for calling the Counter obj's underlying member method code with example usage: obj.serialize() and returns: parent_ser