class_docstr: A very general abstract class representing a metric which can be
  accumulated.
docstr: Compute and return the metric. Optionally also call `self.reset`.
code: def get_metric(self, reset: bool):
      """
      Compute and return the metric. Optionally also call `self.reset`.
      """
      raise NotImplementedError
  
file_path: allennlp/allennlp/training/metrics/metric.py
imports: from typing import Iterable, Optional
  import torch
  from allennlp.common.registrable import Registrable
label_desc: Use image node_id 2 for calling the Metric obj's underlying member method code with example usage: obj.get_metric(reset) without return types