code: def testValidChannel(self):
      instance_a = _MyType()
      instance_b = _MyType()
      chnl = channel.Channel(_MyType).set_artifacts(
          [instance_a, instance_b]
      )
      self.assertEqual(chnl.type_name, "MyTypeName")
      self.assertCountEqual(chnl.get(), [instance_a, instance_b])
  
imports: from unittest import mock
  import tensorflow
  from tfx.dsl.input_resolution import resolver_op
  from tfx.dsl.placeholder import placeholder
  from tfx.types import artifact
  from tfx.types import channel
  from tfx.types import resolved_channel
  from google.protobuf import struct_pb2
  from ml_metadata.proto import metadata_store_pb2
label_desc: Use image node_id 1 for calling the ChannelTest obj's underlying member method code with example usage: obj.testValidChannel() without return types