code: def update(self, strategy):
      self._metric.update()
  
imports: import GPUtil
  from threading import Thread
  import time
  import warnings
  from typing import Optional, TYPE_CHECKING, List
  from avalanche.evaluation import Metric, PluginMetric, GenericPluginMetric
  from avalanche.evaluation.metric_results import MetricResult
label_desc: Use image node_id 2 for calling the GPUPluginMetric obj's underlying member method code with example usage: obj.update(strategy) without return types