code: def testPipelineWithLoop(self):
      channel_one = types.Channel(type=_ArtifactTypeOne)
      channel_two = types.Channel(type=_ArtifactTypeTwo)
      channel_three = types.Channel(type=_ArtifactTypeThree)
      component_a = _make_fake_component_instance(
          "component_a", _OutputTypeA, {}, {}
      )
      component_b = _make_fake_component_instance(
          name="component_b",
          output_type=_OutputTypeB,
          inputs={
              "a": component_a.outputs["output"],
              "one": channel_one,
          },
          outputs={"two": channel_two},
      )
      component_c = _make_fake_component_instance(
          name="component_b",
          output_type=_OutputTypeB,
          inputs={
              "a": component_a.outputs["output"],
              "two": channel_two,
          },
          outputs={"three": channel_three},
      )
      component_d = _make_fake_component_instance(
          name="component_b",
          output_type=_OutputTypeB,
          inputs={
              "a": component_a.outputs["output"],
              "three": channel_three,
          },
          outputs={"one": channel_one},
      )
  
      with self.assertRaises(RuntimeError):
          pipeline.Pipeline(
              pipeline_name="a",
              pipeline_root="b",
              components=[
                  component_c,
                  component_d,
                  component_b,
                  component_a,
              ],
              metadata_connection_config=self._metadata_connection_config,
          )
  
imports: import itertools
  import os
  from typing import Any, Dict, Optional, Type
  import tensorflow
  from tfx import types
  from tfx.dsl.components.base import base_beam_component
  from tfx.dsl.components.base import base_component
  from tfx.dsl.components.base import base_executor
  from tfx.dsl.components.base import base_node
  from tfx.dsl.components.base import executor_spec
  from tfx.dsl.placeholder import placeholder
  from tfx.orchestration import metadata
  from tfx.orchestration import pipeline
  from tfx.types.component_spec import ChannelParameter
  from tfx.types.component_spec import ExecutionParameter
  from tfx.utils import test_case_utils
label_desc: Use image node_id 7 for calling the PipelineTest obj's underlying member method code with example usage: obj.testPipelineWithLoop() without return types