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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 pix2ang(nside, ipix, nest=False, lonlat=False):
 """Drop-in replacement for healpy `~healpy.pixelfunc.pix2ang`."""

    lon, lat = healpix_to_lonlat(ipix, nside, order='nested' if nest else 'ring')
    return _lonlat_to_healpy(lon, lat, lonlat=lonlat)