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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_std_0(self, c1, c2, mag):
 """ Common part of equations 27 and 28, pag 82. """

        if mag < 5:
            return c1
        elif mag >= 5 and mag <= 7:
            return c1 + (c2 - c1) * (mag - 5) / 2
        else:
            return c2