def _parse_marc_code(field):
    """Parse marc field and return default indicators if not filled in."""
    field = str(field)
    if len(field) < 4:
        raise Exception('Wrong field code: %s' % field)
    else:
        field += '__'
    tag = field[0:3]
    ind1 = field[3].replace('_', '')
    ind2 = field[4].replace('_', '')
    return tag, ind1, ind2
Parse marc field and return default indicators if not filled in.