Python图形工具turtledrawing国际象棋棋盘

 #编写程序绘制一个国际象棋的棋盘

    
 import turtle
    
 turtle.speed(30)
    
 turtle.penup()
    
 off = True
    
 for y in range(-40, 30 + 1, 10):
    
 	for x in range(-40, 30 + 1, 10):
    
 		if off:
    
 			turtle.goto(x, y)
    
 			turtle.pendown()
    
 			turtle.begin_fill()
    
 			turtle.color("black")
    
 			turtle.forward(10)
    
 			turtle.left(90)
    
 			turtle.forward(10)
    
 			turtle.left(90)
    
 			turtle.forward(10)
    
 			turtle.left(90)
    
 			turtle.forward(10)
    
 			turtle.left(90)
    
 			turtle.end_fill()
    
 			turtle.penup()
    
 		else:
    
 			tu