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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def setup(working_dir, interactive=False):
 """ Do one-time initialization. Call this to set up global state. """

    # set up our implementation
    log.debug("Working dir: {}".format(working_dir))
    if not os.path.exists( working_dir ):
        os.makedirs( working_dir, 0700 )

    node_config = load_configuration(working_dir)
    if node_config is None:
        sys.exit(1)

    log.debug("config\n{}".format(json.dumps(node_config, indent=4, sort_keys=True)))
    return node_config