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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 output(s):
 """ Parse, transform, and pretty print the result """

    p = Parser()
    t = ExpressionsTransformer()

    ast = p.parse(s)
    logging.debug(ast.pretty())
    print(ast.pretty())
    d = t.transform(ast)
    print(json.dumps(d, indent=4))
    return d