How to replace the last (and only last) character in a string?

[Marc 'BlackJack' Rintsch]

In <1178202464.201578.211150 at c35g2000hsg.googlegroups.com>, Johny wrote:

> Let's suppose
> s='12345 4343 454'
> How can I replace the last '4' character?
> I tried
> string.replace(s,s[len(s)-1],'r')
> where 'r' should replace  the last '4'.
> But it doesn't work.
> Can anyone explain why?

Because you can't change strings.  Any function or method that "changes" a
string returns a new and modified copy.  So does the `string.replace()`
function.  And you don't bind the result to a name, so it is "lost".

This is shorter than using `replace()`:

In [9]: s = '12345 4343 454'

In [10]: s = s[:-1] + 'r'

In [11]: s
Out[11]: '12345 4343 45r'

BTW most things in the `string` module are deprecate because they are
available as methods on string objects.

Ciao,
	Marc 'BlackJack' Rintsch