When i define class with list member(in class body, not
in __init__ or other method) that list become common
for all instances of the class. So when i change list
member in one instance it also will changed in all the
other instances. OS - Windows XP(SP2)

[code]
class TestClass:
    t = []
    def __init__ (self):
        pass

a = TestClass()
b = TestClass()
a.t.append(123)
print b.t
[/code]

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user_id=31435

Closing as Not-a-Bug.  That's exactly what should happen. 
If you want a different `t` per instance, use a different
`t` per instance instead of sharing a common `t` across all
instances  -- you simply got what you asked for here.  If
that's not what you want, then, e.g., put "self.t = []" in
your __init__ method.