"""python 2.7"""

class ABMixin:
    AttributeChanges = [1]
    AttributeDontChangeImmutable = 1
    def __init__(self):
        self.AttributeDontChange = [1]
    
class A(object,ABMixin):
    def __init__(self):
        ABMixin.__init__(self)
        
class B(object,ABMixin):
    def __init__(self):
        ABMixin.__init__(self)   
        
a = A()
b = B()

print a.AttributeChanges,a.AttributeDontChange,a.AttributeDontChangeImmutable
print b.AttributeChanges,b.AttributeDontChange,b.AttributeDontChangeImmutable

a.AttributeChanges[0] = 2
a.AttributeDontChange[0] = 2
a.AttributeDontChangeImmutable = 2

print a.AttributeChanges,a.AttributeDontChange,a.AttributeDontChangeImmutable
print b.AttributeChanges,b.AttributeDontChange,b.AttributeDontChangeImmutable