How can I make my (python)balls stay in the box?

Question

Besides the sussy title (sorry I had no better way to put it) I'm doing a project where I have to keep bouncy balls bouncing in a square. This is my code (pls use the same turtle names)

import turtle
import random

turt = turtle.Turtle()
tart = turtle.Turtle()
screen = turtle.Screen()
turt.speed('fastest')
tart.speed('fastest')

turt.penup()
turt.goto(-250,250)
turt.pendown()
tart.penup()
tart.color("red")
tart.pensize(10)
tart.shape("circle")
for i in range(4):
  turt.forward(450)
  turt.right(90)
  
def up():
    turt.setheading(90)
    if turt.ycor() < 240:
        tart.forward(1)

def down():
    turt.setheading(270)
    if -240 < tart.ycor():
        tart.forward(1)

def left():
    turt.setheading(180)
    if -240 < turt.xcor():
        tart.forward(1)

def right():
    tart.setheading(0)
    if turt.xcor() < 240:
        tart.forward(1)


screen.onkey(up, 'w')
screen.onkey(down, 's')
screen.onkey(left, 'a')
screen.onkey(right, 'd')


screen.mainloop()

tart.right(
  random.randint(1,359)
)
tart.pendown()
while True:
  tart.forward(10)

I just want the ball to stop bouncing for now at the square

Answer 1

You have turt and tart names mixed up in the movement functions (better names would help!!) and the bounding coordinates are wrong. Below I also added a listen() because as is the keys didn't work and increased the forward size because it was really slow.

import turtle
import random

turt = turtle.Turtle()
tart = turtle.Turtle()
screen = turtle.Screen()
turt.speed('fastest')
tart.speed('fastest')

turt.penup()
turt.goto(-250,250)
turt.pendown()
tart.penup()
tart.color("red")
tart.pensize(10)
tart.shape("circle")
for i in range(4):
  turt.forward(450)
  turt.right(90)

speed = 10

def up():
    tart.setheading(90)
    if tart.ycor() < 240:
        tart.forward(speed)

def down():
    tart.setheading(270)
    if tart.ycor() > -190:
        tart.forward(speed)

def left():
    tart.setheading(180)
    if tart.xcor() > -240:
        tart.forward(speed)

def right():
    tart.setheading(0)
    if tart.xcor() < 190:
        tart.forward(speed)


screen.onkey(up, 'w')
screen.onkey(down, 's')
screen.onkey(left, 'a')
screen.onkey(right, 'd')

screen.listen()
screen.mainloop()

tart.right(
  random.randint(1,359)
)
tart.pendown()
while True:
  tart.forward(10)