class_docstr: The Epoch CPU usage metric.
  This plugin metric only works at training time.
  
  The average usage will be logged after each epoch.
class_docstr_tok: ["The","Epoch","CPU","usage","metric",".","This","plugin","metric","only","works","at","training","time",".","The","average","usage","will","be","logged","after","each","epoch","."]
code: def before_training_epoch(self, strategy):
      super().before_training_epoch(strategy)
      self.update(strategy)
  
imports: import os
  import warnings
  from typing import Optional, List
  from psutil import Process
  from avalanche.evaluation import Metric, PluginMetric, GenericPluginMetric
  from avalanche.evaluation.metrics import Mean
label_desc: Use image node_id 2 for calling the EpochCPUUsage obj's underlying member method code with example usage: obj.before_training_epoch(strategy) without return types