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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 not_next(e):
 """ Create a PEG function for negative lookahead. """

    def match_not_next(s, grm=None, pos=0):
        try:
            e(s, grm, pos)
        except PegreError as ex:
            return PegreResult(s, Ignore, (pos, pos))
        else:
            raise PegreError('Negative lookahead failed', pos)
    return match_not_next