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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 _is_significant(change, significance):
 """ Return True if a change is genuinely significant given our tolerance. """

    try:
        a = float(change['from'])
        b = float(change['to'])

    except ValueError:
        return True

    return abs(a - b) > 10 ** (-significance)