from turtle import *
tracer(0)
r = 25
for i in range(10):
    fd(10 * r)
    for j in range(2):
        fd(10 * r)
        rt(90)
up()
for x in range(-5, 25):
    for y in range(-20, 5):
        goto(x * r, y * r)
        dot(3, 'blue')
goto(0, 0)
update()
exitonclick()