save project

my_tree.py

+import turtle
+import random
+color=["snow","lightcoral","mistyrose","cornflowerblue","slateblue","lightskyblue","azure","lavender"]
+def tree(n):
+    if n>=0:
+        if n<=12:           
+            pen.pencolor(random.choice((color)))
+            pen.pensize(n/3)
+        else:
+            pen.pencolor('sienna')  
+            pen.pensize(n/10)
+        pen.forward(n)
+        a=random.randint(0,30)
+        b=random.randint(1,15)
+        pen.right(a)
+        tree(n-b)
+        pen.lt(a*2)
+        tree(n-b)
+        pen.rt(a)
+        pen.up()
+        pen.bk(n)
+        pen.down()
+pen=turtle.Turtle()
+pen.color('sienna')
+# 画布大小
+w = turtle.Screen()
+w.bgcolor('wheat')      # wheat小麦
+
+# 移动到起点
+pen.left(90)
+pen.up()
+pen.backward(150)    # 后退
+pen.down()
+tree(60)
+turtle.done()