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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 xyz2lonlat(x, y, z):
 """Convert cartesian to lon lat."""

    lon = xu.rad2deg(xu.arctan2(y, x))
    lat = xu.rad2deg(xu.arctan2(z, xu.sqrt(x**2 + y**2)))
    return lon, lat