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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 extract_isosurface(pvol):
 """ Extracts the largest isosurface from a volume. The following example illustrates one of the usage scenarios: .. code-block:: python :linenos: from geomdl import construct, multi from geomdl.visualization import VisMPL # Assuming that "myvol" variable stores your spline volume information isosrf = construct.extract_isosurface(myvol) # Create a surface container to store extracted isosurface msurf = multi.SurfaceContainer(isosrf) # Set visualization components msurf.vis = VisMPL.VisSurface(VisMPL.VisConfig(ctrlpts=False)) # Render isosurface msurf.render() :param pvol: input volume :type pvol: abstract.Volume :return: isosurface (as a tuple of surfaces) :rtype: tuple """

    if pvol.pdimension != 3:
        raise GeomdlException("The input should be a spline volume")
    if len(pvol) != 1:
        raise GeomdlException("Can only operate on single spline volumes")

    # Extract surfaces from the parametric volume
    isosrf = extract_surfaces(pvol)

    # Return the isosurface
    return isosrf['uv'][0], isosrf['uv'][-1], isosrf['uw'][0], isosrf['uw'][-1], isosrf['vw'][0], isosrf['vw'][-1]