code: def compute(self):
      return self.list_[self.index]
  
imports: import os
  import numpy
  import pytest
  import torch
  from pytest import approx
  from sklearn.metrics import f1_score, precision_score, recall_score
  import ignite.distributed
  from ignite.engine import Engine
  from ignite.metrics import Accuracy, Metric, MetricsLambda, Precision, Recall
label_desc: Use image node_id 4 for calling the ListGatherMetric obj's underlying member method code with example usage: obj.compute() and returns: self