code: def test_with_handler(self):
      if sys.version_info[0] >= 3:
          callback = PyCM()
          callback.with_handler("test")
          self.assertTrue("test" in callback._handlers)
  
imports: import sys
  from unittest import TestCase
  from mock import MagicMock, patch, ANY
  import torchbearer
  from torchbearer.callbacks import PyCM
  import matplotlib.pyplot
label_desc: Use image node_id 6 for calling the TestPyCM obj's underlying member method code with example usage: obj.test_with_handler() without return types