Fastest way to insert these dashes in python string?

Question

So I know Python strings are immutable, but I have a string:

c[\'date\'] = \"20110104\"

Which I would like to convert to

c[\'da         


        

Answer 1

I'm not usually the guy saying "use regex," but this is a good use-case for it:

import re    
c['date']=re.sub(r'.*(\w{4})(\w{2})(\w{2}).*',r"\1-\2-\3",c['date'])