What is the Python equivalent of Perl's ucfirst() or s///e?

If what you are interested in is upcasing every first character and lower casing the rest (not exactly what the OP is asking for), this is much cleaner:

string.title()

How about:

s = "i'm Brian, and so's my wife!"
print s[0].upper() + s[1:]

The output is:

I'm Brian, and so's my wife!

Just use string slicing:

s[0].upper() + s[1:]

Note that strings are immutable; this, just like capitalize(), returns a new string.