In Python `+=` doesn't return anything either.
- Error: expression 'x' is of type 'y' and has to be used (or disca... Charles
- Error: expression 'x' is of type 'y' and has to be used (or ... Isofruit
- Error: expression 'x' is of type 'y' and has to be used ... Isofruit
- Error: expression 'x' is of type 'y' and has to be u... Charles
- Error: expression 'x' is of type 'y' and has to ... Isofruit
- Error: expression 'x' is of type 'y' and ha... Araq
