4.彩色螺旋线.py

import turtle
import time

turtle.pensize(2)
turtle.bgcolor("black")
colors = ["red", "yellow", 'purple', 'blue']
turtle.tracer(False)
for x in range(400):
    turtle.forward(2 * x)
    turtle.color(colors[x % 4])
    turtle.left(89)  # 变换数字会有不同的效果
turtle.tracer(True)
turtle.done()