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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_sigma_0(self, C, mag, vs30measured):
 """ Equation 27, page 82. """

        s1 = np.zeros_like(vs30measured, dtype=float)
        s2 = np.zeros_like(vs30measured, dtype=float)

        idx = vs30measured == 1
        s1[idx] = C['s1mea']
        s2[idx] = C['s2mea']

        idx = vs30measured == 0
        s1[idx] = C['s1est']
        s2[idx] = C['s2est']

        return self._compute_std_0(s1, s2, mag)