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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_stack_id(self, value, values, height):
 """ Returns the index of the column representation of the given value And we are looking for the index value of 21: This function will return index 20 """


        def step(values, height):
            step_range = max(values) - min(values)
            return (((step_range / float((len(self.__list) * height) - 1)))
                    or 1)

        step_value = step(values, height)
        return int(round((value - min(values)) / step_value))