auto save

my_tree.py

 import turtle
+import random
 
 pen = turtle.Turtle()
 pen.color('sienna')
@@ -6,10 +7,27 @@ pen.color('sienna')
 w = turtle.Screen()
 w.bgcolor('wheat')      # wheat小麦
 
+
+def tree(n):
+    if n >= 50:
+        pen.forward(n)
+        angle = random.randint(0,30)
+        len = random.randint(1,15)
+        pen.right(angle)
+        tree(n-len)
+        pen.left(2*angle)
+        tree(n-len)
+        pen.right(angle)
+        pen.up()
+        pen.backward(n)
+        pen.down()
 # 移动到起点
 pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
 
+tree(100)
+
+
 turtle.done()