from turtle import *
z= 30
tracer(100)
for _ in range(4):
    fd(5*z)
    rt(90)
    fd(10*z)
    rt(90)
pu()
goto(0,0)
for x in range(-20,20):
    for y in range(-20,20):
        setpos(x*z,y*z)
        dot(2)
screensize(40000,40000)
mainloop()