class_docstr: Base class for all accuracies plugin metrics
class_docstr_tok: ["Base","class","for","all","accuracies","plugin","metrics"]
code: def update(self, strategy):
      self._metric.update(strategy.mb_output, strategy.mb_y)
  
imports: from typing import List, Optional, Union, Dict
  import torch
  from torch import Tensor
  from avalanche.evaluation import Metric, GenericPluginMetric
  from avalanche.evaluation.metrics.mean import Mean
  from collections import defaultdict
label_desc: Use image node_id 4 for calling the AccuracyPluginMetric obj's underlying member method code with example usage: obj.update(strategy) without return types