How to remove extra ',' in tuple in django(python)

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长情又很酷
长情又很酷 2021-01-06 07:45

I have one problem in building a list of id using django. if i choose more than 1 id it ok but if i choose only one it will produce extra \',\' in list.

test         


        
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  •  日久生厌
    2021-01-06 08:04

    (1234,)
    

    is the correct Python representation of a 1-tuple. (1234) would be wrong as that is taken as a simple integer in mathematical parentheses, evaluating to 1234, not a tuple containing it.

    This is different for lists because the square brackets don't have this double purpose of also meaning mathemtical order-of-operations, so whilst [1234] and [1234,] are both valid representations of a length-1-list, the default textual representation can be without the extra comma.

    If you are devising your own textual representation of a tuple that does not need to be the same as Python's, you could do eg.:

    '(%s)' % ', '.join(map(repr, testa))
    

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