[Solved] How can i change the position of substring within a string in Python?

You can split the string into a list of substrings:

>>> s="xxxxxxxx,yyyyyyyyyyyy,zzzzzzzzz"

>>> parts = s.split(',')
>>> parts
['xxxxxxxx', 'yyyyyyyyyyyy', 'zzzzzzzzz']

Then you can re-order:

>>> reordered = parts[0] + parts[2] + parts[1]
>>> reordered
['xxxxxxxx', 'zzzzzzzzz', 'yyyyyyyyyyyy']

And rejoin:

>>> ','.join(reordered)
'xxxxxxxx,zzzzzzzzz,yyyyyyyyyyyy'