code: def test_start_returns_self(self):
      monitor = resources.ResourceMonitor()
      self.assertIs(monitor.start(), monitor)
  
file_path: deepvariant/deepvariant/resources_test.py
imports: import resource
  from unittest import mock
  from absl.testing import absltest
  import contextlib2
  from deepvariant import resources
label_desc: Use image node_id 3 for calling the ResourcesTest obj's underlying member method code with example usage: obj.test_start_returns_self() without return types