save project

diy1.py

 
-a=1
+
 import turtle
 
 pen = turtle.Pen()
+colors=["black","white"]
 # 请创造师在下面接着创作
-for i in range(3000):
-    pen.forward(a)
+for i in range(1,3000,5):
+    pen.color(colors[i%2])
+    pen.forward(i)
     pen.right(91)
-    a+=5
+