code: def n(self) -> int:
      return self._weight
  
file_path: ray/python/ray/data/_internal/size_estimator.py
imports: from typing import Any, List
  import ray
  from ray import cloudpickle
label_desc: Use image node_id 3 for calling the RunningMean obj's underlying member method code with example usage: obj.n() and returns: self