def follow_line(instructions): pos = Coord(0, 0) for inst in instructions.split(','): direction = inst[0] distance = int(inst[1:]) for _ in range(distance): if direction == 'U': pos = pos.up() elif direction == 'R': pos = pos.right() elif direction == 'D': pos = pos.down() elif direction == 'L': pos = pos.left() yield pos