save project

my_tree.py

+import turtle
+import random
+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()
+def tree(n):
+    if n>=0:
+        a=random.randint(0,30)
+        l=random.randint(0,15)
+        pen.pensize(l*5)
+        pen.forward(n)
+        if l<=13:
+            pen.color('sienna')
+            pen.right(a)
+            tree(n-l)
+            pen.left(2*a)
+            tree(n-l)
+            pen.right(a)
+            pen.up()
+            pen.backward(n)
+            pen.down()
+        else:
+            pen.pensize(l*10)
+            pen.pencolor('snow')
+            pen.right(a)
+            tree(n-l)
+            pen.left(2*a)
+            tree(n-l)
+            pen.right(a)
+            pen.up()
+            pen.backward(n)
+            pen.down()
+tree(60)
+turtle.done()
+