class_docstr: RunState is used to save the result of every running step
  Args:
      length (int): the number of fetch result
code: def __add__(self, other):
      self.run_step += other.run_step
      self.run_examples += other.run_examples
      for index in range(len(self.run_results)):
          self.run_results[index] += other.run_results[index]
      return self
  
file_path: PaddleHub/paddlehub/compat/task/task_utils.py
imports: import copy
  import time
  from typing import Any
  import paddle.utils.unique_name
label_desc: Use image node_id 2 for calling the RunState obj's underlying member method code with example usage: obj.__add__(other) and returns: self