Python assignment operator: Right operand is also modified when Left operand is modified

Question

I am doing this simple thing, but I don't expect the right operand (apples) to be modified when I modify the left operand(bananas).

>> apples = [1,2,3,4,5]
>> bananas = apples
>> bananas.remove(3)
>> bananas 
   [1,2,4,5]
>> apples 
   [1,2,4,5]

apples should be [1,2,3,4,5] instead of [1,2,4,5].

Please comment on this.

Regards.

https://rg03.wordpress.com/2007/04/21/semantics-of-python-variable-names-from-a-c-perspective/ — user2357112, Apr 06 '15 at 07:34

score 1 · Accepted Answer · answered Apr 06 '15 at 07:35

1

Simplest way avoid it use:

bananas = []+apples

answered Apr 06 '15 at 07:35

mmachine

2

To copy a list, usually you use `bananas = apples[:]`. – Daniel Apr 06 '15 at 07:43
To copy a list that might have embedded references use `bananas = copy.deepcopy(apples)` – cdarke Apr 06 '15 at 08:21

1 Answers1