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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 obtain_to(filename):
 """ Return the digital elevation map projected to the lat lon matrix coordenates. Keyword arguments: filename -- the name of a netcdf file. """

    root, _ = nc.open(filename)
    lat, lon = nc.getvar(root, 'lat')[0,:], nc.getvar(root, 'lon')[0,:]
    nc.close(root)
    return obtain(lat, lon)