我可以把乌龟移到终点，但当乌龟越过终点线时，我的碰撞检测器不工作。它会越过白色的边界线，但当它碰到单词FINISH时，我需要它停止。还需要保持乌龟在边界内。也许我需要解码xcor((算法？请帮忙！
import turtle as trtl
background = trtl.Screen()
background.screensize(canvwidth =1, canvheight=1)
boundary = trtl.Turtle()
#draw square boundary
def squareDraw(boundary):
boundary.speed(0)
boundary.pu()
boundary.goto(-175,160)
boundary.pd()
for i in range(4):
boundary.color("white")
boundary.forward(315)
boundary.right(90)
boundary.ht()
squareDraw(boundary)
boundary.pu()
boundary.goto(-40,160)
boundary.color("red")
boundary.pd()
boundary.write("FINISH!", font=40)
#moving square coordinates
turtleCoordinate = (-25,-120)
turtleShape = trtl.Turtle()
turtleShape.left(90)
turtleShape.shape("turtle")
turtleShape.color("orange")
turtleShape.shapesize(1.75)
turtleShape.pu()
turtleShape.goto(turtleCoordinate)
#boundarys for answers
obstacles = trtl.Turtle()
obstacles.speed(0)
obstacles.pu()
obstacles.goto(-120,90)
obstacles.color("white")
for i in range(4):
obstacles.pd()
obstacles.forward(50)
obstacles.right(90)
obstacles.ht()
obstacles.pu()
obstacles.goto(0,12)
obstacles.color("white")
for i in range(4):
obstacles.pd()
obstacles.forward(40)
obstacles.right(90)
obstacles.ht()
obstacles.pu()
obstacles.goto(68,125)
obstacles.color("white")
for i in range(4):
obstacles.pd()
obstacles.forward(30)
obstacles.right(90)
obstacles.ht()
#1st math problem
firstProblem = []
secondProblem = [8,2,1]
#steps = 0
#while steps < 100:
for turtleShape in firstProblem:
turtleShape.forward(4)
if turtleShape.xcor() > 140:
turtleShape.right(180)
elif turtleShape.xcor() > -175:
turtleShape.left(180)
if turtleShape.ycor() > 160:
turtleShape.right(180)
elif turtleShape.ycor() < -155:
turtleShape.right(180)
#actions to move turtle
move_speed = 15
def left():
turtleShape.left(move_speed)
def right():
turtleShape.right(move_speed)
def forward():
turtleShape.forward(move_speed)
def backward():
turtleShape.backward(move_speed)
background.onkey(forward, "Up")
background.onkey(backward, "Down")
background.onkey(left, "Left")
background.onkey(right, "Right")
background.listen()
steps = 0
for turtleShape in firstProblem:
stepMax = 15
if steps > stepMax:
turtleShape.forward(3)
background = trtl.Screen()
background.mainloop()
移动left((、right((、forward((、backward((函数中的边界检查。示例：在forward函数中，您将检查是否正在击中边界，并且只按分钟(move_speed，boundary-y position(向前移动。这会让你完全停在边界上。