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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 _compute_a22_factor(self, imt):
 """ Compute and return the a22 factor, equation 20, page 80. """

        if imt.name == 'PGV':
            return 0.0
        period = imt.period
        if period < 2.0:
            return 0.0
        else:
            return 0.0625 * (period - 2.0)