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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 lonlat2xyz(lon, lat):
 """Convert lon lat to cartesian."""

    lat = xu.deg2rad(lat)
    lon = xu.deg2rad(lon)
    x = xu.cos(lat) * xu.cos(lon)
    y = xu.cos(lat) * xu.sin(lon)
    z = xu.sin(lat)
    return x, y, z