def unpack_bytes(packed, offset):
    """
    Unpacks a list of bytes from the specified numpy arrays of packed byte
    data and corresponding offsets. See :ref:`sec_encoding_ragged_columns` for details
    of this encoding.

    :param numpy.ndarray packed: The flattened array of byte values.
    :param numpy.ndarray offset: The array of offsets into the ``packed`` array.
    :return: The list of bytes values unpacked from the parameter arrays.
    :rtype: list[bytes]
    """
    # This could be done a lot more efficiently...
    ret = []
    for j in range(offset.shape[0] - 1):
        raw = packed[offset[j] : offset[j + 1]].tobytes()
        ret.append(raw)
    return ret