def _normalize_default(value, dtype):

    # Create NumPy objects as defaults
    # This is better in order to serialize them as attributes
    if value is None:
        value = 0
    basedtype = dtype.base
    try:
        default = numpy.array(value, dtype=basedtype)
    except ValueError:
        array = numpy.array(value)
        if array.shape != basedtype.shape:
            raise
        # Maybe nested dtype with "scalar" value.
        default = numpy.array(value, dtype=basedtype.base)
    # 0-dim arrays will be representented as NumPy scalars
    # (PyTables attribute convention)
    if default.shape == ():
        default = default[()]
    return default
Return `value` as a valid default of NumPy type `dtype`.
dataset/ETHPy150Open PyTables/PyTables/tables/atom.py/_normalize_default