[issue5620] The attribute's action of an object is not correct.

[edmundy]

New submission from edmundy <yong.sunny at 163.com>:

The following is the test code.

class C1:
	myurl = []	
	def test(self):
		url = [5,6,7]
		self.myurl.extend(url)		
def testv():
	c = C1()
	c.test()
	print(c.myurl)
	
i = 0
while i<10 :
	testv()
	i = i+1

The output is :

[5, 6, 7]
[5, 6, 7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 
7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 
7, 5, 6, 7]
[5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 7, 5, 6, 
7, 5, 6, 7, 5, 6, 7]

The myurl of class C1 is not set to [] when a new object is created.
All objects use the same memory.

----------
components: None
messages: 84765
nosy: Yong yang
severity: normal
status: open
title: The attribute's action of an object is not correct.
type: behavior
versions: Python 3.0

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue5620>
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