class IAT( object):

    iat = []

    def __init__( self):
        print self.iat
        for i in range( 10):
            self.iat.append( i)


x = IAT()
y = IAT()


Output of this program is:
[]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]