auto save

my_tree.py

 import turtle
+import random
 
 pen = turtle.Turtle()
 pen.color('sienna')
 # 画布大小
 w = turtle.Screen()
 w.bgcolor('wheat')      # wheat小麦
-
+pen.speed(0)
 # 移动到起点
 pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
-def tree(n):
-    if n>=25:
-        if n<=40:
-            pen.color("pink")
+
+def tree(n,s):
+    if n>=10:
+        if n<=20:
+            c=random.choice(["snow","lightcoral"])
+            pen.color(c)
+            
+            pen.pensize(3)
         else:
             pen.color("sienna")
+            s=s/3
+            pen.pensize(s)
         pen.forward(n)
-        pen.right(30)
-        tree(n-15)
-        pen.left(60)
-        tree(n-15)
-        pen.right(30)
+        a=random.randint(5,30)
+        b=random.randint(1,15)
+        pen.right(a)
+        tree(n-15,s)
+        pen.left(2*a)
+        tree(n-15,s)
+        pen.right(a)
         pen.up()
         pen.backward(n)
         pen.down()
-tree(100)
+tree(100,10)
 turtle.done()