def METHOD_NAME(tag: Tag, size: int) -> bytes:
    """
    Pack contextual tag.
    :param tag: BER tag
    :param size: the size of the contextual packet.
    """
    return Uint8.pack((Class.BER_CLASS_CTXT | PC.BER_CONSTRUCT) | (Tag.BER_TAG_MASK & tag)) + writeLength(size)