def METHOD_NAME(pipeline_dir):
    # Construct 4-node pipeline consisting of 3 notebooks and 1 python script.
    # This pipeline is "diamond shaped" with node1 feeding nodes 2 and 3, each then
    # feeding node4.
    node1 = NotebookNode("node1", num_outputs=2)
    node2 = PythonNode("node2", num_outputs=2, input_nodes=[node1])
    node3 = NotebookNode("node3", num_outputs=2, input_nodes=[node1])
    node4 = NotebookNode("node4", num_outputs=2, input_nodes=[node2, node3])
    nodes = [node1, node2, node3, node4]
    pipeline = construct_pipeline("p1", nodes=nodes, location=pipeline_dir)
    LocalPipelineProcessor(root_dir=pipeline_dir).process(pipeline)
    # Confirm outputs
    for node in nodes:
        for output in node.outputs:
            assert os.path.exists(os.path.join(pipeline_dir, output))