code: def testFilteredOut(self):
      result = image_differencer.image_differencer(
          path=proto_diff.ProtoPath(("observation", "actions", 1)),
          proto_a=None,
          proto_b=None,
      )
      self.assertIsNone(result)
  
file_path: pysc2/pysc2/lib/image_differencer_test.py
imports: from absl.testing import absltest
  import numpy
  from pysc2.lib import image_differencer
  from pysc2.lib import proto_diff
  from s2clientprotocol import common_pb2
  from s2clientprotocol import sc2api_pb2
  from s2clientprotocol import spatial_pb2
label_desc: Use image node_id 1 for calling the ImageDifferencerTest obj's underlying member method code with example usage: obj.testFilteredOut() without return types