三層迴圈 畫多邊形

import turtle
t=turtle.Pen()
t.penup()
t.setpos(-200,-200)
t.clear()
t.pendown()
for j in range(1,4):
    for slides in range(3,5):
        angle=360/slides
        for i in range(1,slides+1):
            t.forward(200)
            t.left(angle)
    t.forward(200)
turtle.mainloop()
#turtle.bye()