save project

my_tree.py

 import turtle
+import random
+lsit=["snow","lightcoral"]
+def tree(n):
+
+    if n >=10:
+        if n<=20:
+            pen.pencolor(random.choice(list1))
+            pen.pensize(n/3)
+        else:
+            pen.pencolor("sienna")
+            pen.pensize(n/10)
+        jiaodu = random.randint(5,30)
+        changdu = random.randint(5,15)
+        pen.forward(n)
+        pen.right(jiaodu)
+        tree(n-changdu)
+
+        pen.left(jiaodu*2)
+        tree(n-changdu)
+
+        pen.right(jiaodu)
+        pen.up()
+        pen.backward(n)
+        pen.down()
+
 
 pen = turtle.Turtle()
 pen.color('sienna')
@@ -12,16 +37,8 @@ pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
-pen.forward(100)
-pen.right(30)
-pen.forward(50)
-pen.backward(50)
-pen.left(60)
-pen.forward(50)
-pen.backward(50)
-pen.right(30)
-pen.backward(100)
 
+tree(90)