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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 f_aoi(surface_tilt, surface_azimuth, solar_zenith, solar_azimuth):
 """ Calculate angle of incidence :param surface_tilt: :param surface_azimuth: :param solar_zenith: :param solar_azimuth: :return: angle of incidence [deg] """

    return pvlib.irradiance.aoi(surface_tilt, surface_azimuth,
                                solar_zenith, solar_azimuth)