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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 solar_zenith_analytical(latitude, hourangle, declination):
 """ Analytical expression of solar zenith angle based on spherical trigonometry. .. warning:: The analytic form neglects the effect of atmospheric refraction. Parameters latitude : numeric Latitude of location in radians. hourangle : numeric Hour angle in the local solar time in radians. declination : numeric Declination of the sun in radians. Returns ------- zenith : numeric Solar zenith angle in radians. References [1] J. A. Duffie and W. A. Beckman, "Solar Engineering of Thermal Processes, 3rd Edition" pp. 14, J. Wiley and Sons, New York (2006) [2] J. H. Seinfeld and S. N. Pandis, "Atmospheric Chemistry and Physics" p. 132, J. Wiley (1998) [3] Daryl R. Myers, "Solar Radiation: Practical Modeling for Renewable Energy Applications", p. 5 CRC Press (2013) `Wikipedia: Solar Zenith Angle <https://en.wikipedia.org/wiki/Solar_zenith_angle>`_ `PVCDROM: Sun's Position <http://www.pveducation.org/pvcdrom/2-properties-sunlight/suns-position>`_ See Also -------- declination_spencer71 declination_cooper69 hour_angle """

    return np.arccos(
        np.cos(declination) * np.cos(latitude) * np.cos(hourangle) +
        np.sin(declination) * np.sin(latitude)
    )