Is Python list variable not passing by reference? -

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i'm confused pass-by-ref , pass-by-value in python. in following code, when listb = lista, listb should being assigned pointer (reference) list in lista variable. changes listb should reflected on lista. however, not case in test. doing wrong code? i'm running python 3.4.3

>>> lista = [1,2,3] >>> listb = lista >>> lista = [4,5,6] >>> print(lista, listb) [4, 5, 6] [1, 2, 3] >>> listb[0] ='new' >>> print(lista, listb) [4, 5, 6] ['new', 2, 3]

when lista = [4,5,6], reference lista (that assigned listb) no longer points lista, since replaced lista new list.

if remove line, find works expected.


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