Swapping every second character in a string in Python

Question

I have the following problem: I would like to write a function in Python which, given a string, returns a string where every group of two characters is swapped.

For example given "ABCDEF" it returns "BADCFE".

The length of the string would be guaranteed to be an even number.

Can you help me how to do it in Python?

Answer 1

To add another option:

>>> s = 'abcdefghijkl'
>>> ''.join([c[1] + c[0] for c in zip(s[::2], s[1::2])])
'badcfehgjilk'