save project

my_tree.py

 import turtle
 import turtle
+import random
 
 
 pen = turtle.Turtle()
 pen = turtle.Turtle()
 pen.color('sienna')
 pen.color('sienna')
 # 画布大小
 # 画布大小
 w = turtle.Screen()
 w = turtle.Screen()
-w.bgcolor('green' )      # wheat小麦
+w.bgcolor('blue')    # wheat小麦
 
 
 # 移动到起点
 # 移动到起点
 pen.left(90)
 pen.left(90)
@@ -14,15 +15,22 @@ pen.down()
 pen.speed(100)
 pen.speed(100)
 
 
 def tree(n):
 def tree(n):
-    if n >=50:
+    if n >=0:
+        if n <12:
+            pen.pensize(n/3)
+            colors=['snow','orange']
+            pen.pencolor(random.choice(colors))
+        else:
+            pen.pensize(n/10)
+            pen.color('sienna')
+        length=random.randint(1,15)
+        rangle=random.randint(0,30)
         pen.forward(n)
         pen.forward(n)
-        pen.right(30)
+        pen.right(rangle)
         tree(n-10)
         tree(n-10)
-        pen.left(60)
+        pen.left(2*rangle)
         tree(n-10)
         tree(n-10)
-        
-        
-        pen.right(30)
+        pen.right(rangle)
         pen.up()
         pen.up()
         pen.backward(n)
         pen.backward(n)
         pen.down()
         pen.down()