save project

2.py

+import turtle
+a = ['green','red','orange','yellow']
+pen = turtle.Pen()
+screen = turtle.Screen()
+screen.bgcolor('black')
+pen.speed(100)
+for i in range(1,300):
+    pen.color(a[i%4])
+    pen.forward(i)
+    pen.right(91)
+penhide()
+turtle.down()
\ No newline at end of file

3.py

+import turtle
+pen = turtle.Pen()
+screen = turtle.Screen()
+screen.bgcolor('black')
+pen.speed(100)
+pen.forward(100)
+turtle.down()
\ No newline at end of file

4.py

+a = ['刘备','关羽','张飞']
+a[0] = '关羽'
+a[1] = '刘备'
+print(a)
\ No newline at end of file