Python 3 对象:2

#!/usr/bin/python3

class Point:
   def __init__( self, x=0, y=0):
      self.x = x
      self.y = y
   def __del__(self):
      class_name = self.__class__.__name__
      print (class_name, "对象将被销毁 object destroied")

pt1 = Point()
pt2 = pt1
pt3 = pt1
print (id(pt1), id(pt2), id(pt3)) 
del pt1
del pt2
del pt3