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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 help_message():
 """Return help output."""

    parser = autopep8.create_parser()
    string_io = io.StringIO()
    parser.print_help(string_io)
    # Undo home directory expansion.
    return string_io.getvalue().replace(os.path.expanduser('~'), '~')