auto save

1.py

+        pen.forward(n)
+        pen.right(30)
+        tree(n-10)
+        pen.left(60)
+        tree(n-10)
+        pen.right(30)
+        pen.up()
+        pen.backward(n)
+        pen.down()
\ No newline at end of file

my_tree.py

 import turtle
+import random
 
 pen = turtle.Turtle()
 pen.color('sienna')
@@ -11,5 +12,30 @@ pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
+pen.speed(10)
+def tree(n):
+    if n >= 0:
+        pen.speed(10)
+        colors = ['snow' , 'lightcoral']
+        if n >= 10:
+            pen.pencolor('sienna')
+        else:
+            pen.pencolor(random.choice(colors))
+            pen.pensize(10)
+        jiaodu = random.randint(10,30)
+        lengt = random.randint(0,10)
+        pen.pensize(n/10)
+        pen.forward(n)
+        pen.right(jiaodu)
+        tree(n-lengt)
+        pen.left(2*jiaodu)
+        tree(n-lengt)
+        pen.right(jiaodu)
+        pen.up()
+        pen.backward(n)
+        pen.down()
 
+        
+
+tree(38)
 turtle.done()