Any better way for doing a = b + a?

Question

I\'m using PyCharm and I have this statement:

a = \'foo\'
b = \'bar\'
a = b + a

and PyCharm highlights the last line saying that:

Answer 1

Just ignore PyCharm, it is being obtuse. The remark clearly doesn't apply when the operands cannot just be swapped.

The hint works for numeric operands because a + b produces the same result as b + a, but for strings addition is not commutative and PyCharm should just keep out of it.

If you really want to avoid the message, you could use string formatting:

a = '{}{}'.format(b, a)

but I'd not bother, really.