Помогите!!!!!!!!!!!!!!!!!!!!

import turtle, math
trt = turtle.Turtle()
lst = [-1,0,1]
step = 20
for i in range(3):
    trt.penup()
    trt.goto(step*lst[i]*4,0)
    trt.setheading(0)
    trt.forward(step*3)
    trt.setheading(0)
    trt.backward(step*1)
    for k in range(4):
        trt.pendown()
        trt.forward(step*2)
        trt.left(45)
        trt.forward(step*math.sqrt(8))
        trt.left(45)
turtle.mainloop()