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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 _build_repeat_suffix(iteration, count):
 """ Return the suffix string to identify iteration X out of Y. For example, with a count of 100, this will build strings like "iteration_053" or "iteration_008". :param iteration: Current iteration. :type iteration: `int` :param count: Total number of iterations. :type count: `int` :return: Repeat suffix. :rtype: `unicode` """

    format_width = int(math.ceil(math.log(count + 1, 10)))
    new_suffix = 'iteration_{0:0{width}d}'.format(
        iteration,
        width=format_width
    )
    return new_suffix