auto save

my_tree.py

 import turtle
+import random as r
+co = ['snow', 'lightcoral']
+def tree(n):
+    if n>=0:
+        if n<=12:
+            pen.color(r.choice(co))
+            pen.pensize(n/3)
+        else:
+            pen.color('sienna')
+            pen.pensize(n/10)
+        pen.forward(n)
+        angle = r.randint(0,30)
+        length = r.randint(1,10)
+        pen.right(angle)
+        tree(n-length)
+        pen.left(2*angle)
+        tree(n-length)
+        pen.right(angle)
+        pen.up()
+        pen.bk(n)
+        pen.down()
+
 
 pen = turtle.Turtle()
-pen.color('sienna')
+pen.speed(0.1)
 # 画布大小
 w = turtle.Screen()
 w.bgcolor('wheat')      # wheat小麦
@@ -12,4 +34,7 @@ pen.up()
 pen.backward(150)    # 后退
 pen.down()
 
+
+tree(60)
+
 turtle.done()