class_docstr: Maintains running average for scalar metrics
  
  Call .restart() to clear added values and to start a new round of averaging
docstr: average of all values added since instantiation or last restart call
  
  Returns
  -------
  float
      the current average
docstr_tok: ["average","of","all","values","added","since","instantiation","or","last","restart","call","Returns","--","--","--","-","float","the","current","average"]
code: def value(self) -> float:
      """
      average of all values added since instantiation or last restart call
  
      Returns
      -------
      float
          the current average
      """
      if self._count == 0:
          warnings.warn(f"Nothing have been added. Inf is returned.")
          return float("inf")
      else:
          return self._cum_values / self._count
  
imports: from __future__ import annotations
  import time
  import warnings
  from abc import ABC, abstractmethod
  from typing import Optional, Union
  from torch import Tensor
  from ..engine.distributed import reduce_value
label_desc: Use image node_id 3 for calling the NumericalAverageMeter obj's underlying member method code with example usage: obj.value() and returns: float, unknown