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
+x=["snow","lightcoral"]
+def tree(n):
+    if (n>=0): 
+        if n<=12:
+            x=["snow","lightcoral"]
+            y=random.choice(x)
+            pen.pencolor(y)
+            pen.pensize(n/3)
+        else:
+            pen.pencolor("sienna")
+            pen.pensize(n/10)
+        pen.forward(n)
+        a=random.randint(0,30)
+        l=random.randint(1,15)
+        pen.right(a)
+        tree(n-l)
+        pen.left(a*2)
+        tree(n-l)
+        pen.right(a)
+        pen.up()
+        pen.backward(n)
+        pen.down()
+# 移动到起点
+pen.left(90)
+pen.up()
+pen.backward(150)    # 后退
+pen.down()
+
+tree(100)