Return space group in international table symbol and number as a string.

    If it fails, None is returned.

def get_spacegroup(cell, symprec=1e-5, angle_tolerance=-1.0, symbol_type=0):
    """Return space group in international table symbol and number as a string.

    If it fails, None is returned.
    """
    _set_no_error()

    dataset = get_symmetry_dataset(cell,
                                   symprec=symprec,
                                   angle_tolerance=angle_tolerance)
    if dataset is None:
        return None

    spg_type = get_spacegroup_type(dataset['hall_number'])
    if symbol_type == 1:
        return "%s (%d)" % (spg_type['schoenflies'], dataset['number'])
    else:
        return "%s (%d)" % (spg_type['international_short'], dataset['number'])