def _abbrieviate_direction(ext_dir_str):
    """Convert extended (non-abbrievated) directions to abbrieviation."""
    return ext_dir_str.upper().replace('_', '').replace('-', '').replace(' ',
        '').replace('NORTH', 'N').replace('EAST', 'E').replace('SOUTH', 'S'
        ).replace('WEST', 'W')
