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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 get(self, tag, nth=1):
 """Return n-th value for tag. :param tag: FIX field tag number. :param nth: Index of tag if repeating, first is 1. :return: None if nothing found, otherwise value matching tag. Defaults to returning the first matching value of 'tag', but if the 'nth' parameter is overridden, can get repeated fields."""


        tag = fix_tag(tag)
        nth = int(nth)

        for t, v in self.pairs:
            if t == tag:
                nth -= 1
                if nth == 0:
                    return v

        return None