save project

diy1.py

@@ -5,11 +5,14 @@
 import turtle
 # 请创造师在下面接着创作
 pen=turtle.Pen()
-a=1
-for i in range(300):
-    pen.forward(a)
+screen=turtle.Screen()
+screen.bgcolor("black")
+colors=["red","blue","yellow","green"]
+for i in range(1,300):
+    pen.color(colors[i%4])
+    pen.forward(i)
     pen.right(91)
-    a+=1
+    i+=1
 # 隐藏画笔，保存画布
 pen.hideturtle()
 turtle.done()