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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 get_v_eff_stress_at_depth(self, y_c):
 """ Determine the vertical effective stress at a single depth z_c. :param y_c: float, depth from surface """

        sigma_v_c = self.get_v_total_stress_at_depth(y_c)
        pp = self.get_hydrostatic_pressure_at_depth(y_c)
        sigma_veff_c = sigma_v_c - pp
        return sigma_veff_c