def create_ship_dict(ship_volumes):
    """Creates and returns a dictionay of ship names and volumes with the
    supplied tuple"""
    ship_dict = {}
    for ship, volume in ship_volumes:
        ship = ship.replace(' ', '_')
        ship = ship.replace('-', '_')
        ship = ship.replace("'", '')
        ship = ship.lower()
        ship_dict[ship] = volume
    return ship_dict
