python画10环图

import turtle
t = turtle.Pen()
t.width(5)
t.speed(1)
my_colors = ('red','green','yellow','black','blue','brown',
             'grey','purple','pink','orange')
for i in range(1,11):
    t.penup()
    t.goto(0,-20*i)
    t.pendown()
    t.color(my_colors[i-1])
    t.circle(i*20)
turtle.done()