class_docstr: The abstract class representing a metric which can be accumulated at each batch and calculated at the end
  of the epoch.
docstr: Compute and return the metric. Should not modify the state of metric.
code: def compute(self):
      """
      Compute and return the metric. Should not modify the state of metric.
      """
      pass
  
file_path: poutyne/poutyne/framework/metrics/base.py
imports: from abc import ABC, abstractmethod
  import torch.nn
label_desc: Use image node_id 3 for calling the Metric obj's underlying member method code with example usage: obj.compute() without return types