def setup_ship(self, name, length):
     while True :
         print("Add a " + name + " (length {0}):".format(length))
         start = input("Enter a start coordinate : ")
         end = input("Enter the end coordinate: ")
         ship = Ship(Coord(start), Coord(end))
         if ship.length() != length :
             print("That's not the right length ({0}). Try again.".format(ship.length()))
         else :
             break
     self._my_board.add_ship(ship)