How to use the xgcm.models.mitgcm.utils.parse_meta_file function in xgcm

def _guess_model_dimensions(dirname, is_llc=False):
    try:
        rc_meta = parse_meta_file(os.path.join(dirname, 'RC.meta'))
        if len(rc_meta['dimList']) == 2:
            nz = 1
        else:
            nz = rc_meta['dimList'][2][2]
    except IOError:
        raise IOError("Couldn't find RC.meta file to infer nz.")
    try:
        xc_meta = parse_meta_file(os.path.join(dirname, 'XC.meta'))
        nx = xc_meta['dimList'][0][0]
        ny = xc_meta['dimList'][1][0]
    except IOError:
        raise IOError("Couldn't find XC.meta file to infer nx and ny.")
    if is_llc:
        nface = LLC_NUM_FACES
        ny /= nface
    else:
        nface = None
    return nz, nface, ny, nx

def _guess_model_dimensions(dirname, is_llc=False):
    try:
        rc_meta = parse_meta_file(os.path.join(dirname, 'RC.meta'))
        if len(rc_meta['dimList']) == 2:
            nz = 1
        else:
            nz = rc_meta['dimList'][2][2]
    except IOError:
        raise IOError("Couldn't find RC.meta file to infer nz.")
    try:
        xc_meta = parse_meta_file(os.path.join(dirname, 'XC.meta'))
        nx = xc_meta['dimList'][0][0]
        ny = xc_meta['dimList'][1][0]
    except IOError:
        raise IOError("Couldn't find XC.meta file to infer nx and ny.")
    if is_llc:
        nface = LLC_NUM_FACES
        ny /= nface
    else:

def _guess_layers(dirname):
    """Return a dict matching layers suffixes to dimension length."""
    layers_files = glob(os.path.join(dirname, 'layers*.meta'))
    all_layers = {}
    for fname in layers_files:
        # make sure to exclude filenames such as
        # "layers_surfflux.01.0000000001.meta"
        if not re.search('\.\d{10}\.', fname):
            # should turn "foo/bar/layers1RHO.meta" into "1RHO"
            layers_suf = os.path.splitext(os.path.basename(fname))[0][6:]
            meta = parse_meta_file(fname)
            Nlayers = meta['dimList'][2][2]
            all_layers[layers_suf] = Nlayers
    return all_layers