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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 pfLon(jd, lat, lon):
 """ Returns the ecliptic longitude of Pars Fortuna. It considers diurnal or nocturnal conditions. """

    sun = swe.sweObjectLon(const.SUN, jd)
    moon = swe.sweObjectLon(const.MOON, jd)
    asc = swe.sweHousesLon(jd, lat, lon,
                           const.HOUSES_DEFAULT)[1][0]
    
    if isDiurnal(jd, lat, lon):
        return angle.norm(asc + moon - sun)
    else:
        return angle.norm(asc + sun - moon)