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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 lat_from_inc(inc, a95=None):
 """ Calculate paleolatitude from inclination using the dipole equation Required Parameter inc: (paleo)magnetic inclination in degrees Optional Parameter a95: 95% confidence interval from Fisher mean Returns if a95 is provided paleo_lat, paleo_lat_max, paleo_lat_min are returned otherwise, it just returns paleo_lat """

    rad = old_div(np.pi, 180.)
    paleo_lat = old_div(np.arctan(0.5 * np.tan(inc * rad)), rad)
    if a95 is not None:
        paleo_lat_max = old_div(
            np.arctan(0.5 * np.tan((inc + a95) * rad)), rad)
        paleo_lat_min = old_div(
            np.arctan(0.5 * np.tan((inc - a95) * rad)), rad)
        return paleo_lat, paleo_lat_max, paleo_lat_min
    else:
        return paleo_lat