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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 overflow(self):
 """ Returns true if this BinProxy is for an overflow bin """

        indices = self.hist.xyz(self.idx)
        for i in range(self.hist.GetDimension()):
            if indices[i] == 0 or indices[i] == self.hist.nbins(i) + 1:
                return True
        return False