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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 iterate(self):
 """ Updates values as if we had iterated over the for """

        self.counter += 1
        self.counter0 += 1
        self.revcounter -= 1
        self.revcounter0 -= 1
        self.first = False
        self.last = (self.revcounter0 == self.len_values - 1)