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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_surfaces(pvol):
 """ Extracts surfaces from a volume. :param pvol: input volume :type pvol: abstract.Volume :return: extracted surface :rtype: dict """

    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")

    # Get data from the volume object
    vol_data = pvol.data
    rational = vol_data['rational']
    degree_u = vol_data['degree'][0]
    degree_v = vol_data['degree'][1]
    degree_w = vol_data['degree'][2]
    kv_u = vol_data['knotvector'][0]
    kv_v = vol_data['knotvector'][1]
    kv_w = vol_data['knotvector'][2]
    size_u = vol_data['size'][0]
    size_v = vol_data['size'][1]
    size_w = vol_data['size'][2]
    cpts = vol_data['control_points']

    # Determine object type
    obj = shortcuts.generate_surface(rational)

    # u-v plane
    surflist_uv = []
    for w in range(size_w):
        surf = obj.__class__()
        surf.degree_u = degree_u
        surf.degree_v = degree_v
        surf.ctrlpts_size_u = size_u
        surf.ctrlpts_size_v = size_v
        surf.ctrlpts2d = [[cpts[v + (size_v * (u + (size_u * w)))] for v in range(size_v)] for u in range(size_u)]
        surf.knotvector_u = kv_u
        surf.knotvector_v = kv_v
        surflist_uv.append(surf)

    # u-w plane
    surflist_uw = []
    for v in range(size_v):
        surf = obj.__class__()
        surf.degree_u = degree_u
        surf.degree_v = degree_w
        surf.ctrlpts_size_u = size_u
        surf.ctrlpts_size_v = size_w
        surf.ctrlpts2d = [[cpts[v + (size_v * (u + (size_u * w)))] for w in range(size_w)] for u in range(size_u)]
        surf.knotvector_u = kv_u
        surf.knotvector_v = kv_w
        surflist_uw.append(surf)

    # v-w plane
    surflist_vw = []
    for u in range(size_u):
        surf = obj.__class__()
        surf.degree_u = degree_v
        surf.degree_v = degree_w
        surf.ctrlpts_size_u = size_v
        surf.ctrlpts_size_v = size_w
        surf.ctrlpts2d = [[cpts[v + (size_v * (u + (size_u * w)))] for w in range(size_w)] for v in range(size_v)]
        surf.knotvector_u = kv_v
        surf.knotvector_v = kv_w
        surflist_vw.append(surf)

    # Return shapes as a dict object
    return dict(uv=surflist_uv, uw=surflist_uw, vw=surflist_vw)