auto save

demo.py

+import random
+a = ['lightcoral' ,'snow']
+
+# c=random.randint(0,1)  #生成随机数
+c= random.choice(a)
+print(random.choice(['snow' ,'lightcoral']))
\ No newline at end of file

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
@@ -11,5 +11,28 @@ pen.left(90)
 pen.up()
 pen.up()
 pen.backward(150)    # 后退
 pen.backward(150)    # 后退
 pen.down()
 pen.down()
+pen.speed(0)
+#画二叉树
+def tree(n):
+    if n >= 0:
+        if n <= 12 :
+            pen.pencolor(random.choice(['snow' ,'lightcoral']))
+            pen.pensize(n/3)
+        else:
+            pen.pencolor('sienna')
+            pen.pensize(n/10)
+
+        length = random.randint(0,15)  #长度
+        angle = random.randint(10,20)  #角度
+        pen.forward(n)
+        pen.right(angle)
+        tree(n-length)
+        pen.left(2*angle)
+        tree(n-length)
+        pen.right(angle)
+        pen.penup()
+        pen.bk(n)
+        pen.pendown()
 
 
+tree(80)
 turtle.done()
 turtle.done()