Making letters uppercase using re.sub in python?

Question

In many programming languages, the following

find foo([a-z]+)bar and replace with GOO\\U\\1GAR

will result in the entire match bei

Answer 1

You could use some variation of this:

s = 'foohellobar'
def replfunc(m):
     return m.groups()[0]+m.groups()[1].upper()+m.groups()[2]
re.sub('(foo)([a-z]+)(bar)',replfunc,s)

gives the output:

'fooHELLObar'