code: def test_call(self):
      mean = self.evaluator()
      # main is used as default
      key = "ap/iou=0.50:0.95/area=all/max_dets=100"
      key = "ap/iou=0.50:0.95/area=all/max_dets=100"
      np.testing.assert_equal(
          mean["main/m{}".format(key)], self.expected_ap
      )
      np.testing.assert_equal(mean["main/{}/cls0".format(key)], np.nan)
      np.testing.assert_equal(
          mean["main/{}/cls1".format(key)], self.expected_ap
      )
      np.testing.assert_equal(mean["main/{}/cls2".format(key)], np.nan)
  
imports: import numpy
  import unittest
  import chainer
  from chainer.datasets import TupleDataset
  from chainer.iterators import SerialIterator
  from chainer import testing
  from chainercv.extensions import InstanceSegmentationCOCOEvaluator
  from chainercv.utils.testing import attr
  from chainermn import create_communicator
label_desc: Use image node_id 3 for calling the TestInstanceSegmentationCOCOEvaluator obj's underlying member method code with example usage: obj.test_call() without return types