r'''
(?#First, match the protocol)
(?:https?|ftp)://
(?#Next, check for optional username and/or password)
(?#Note: The following two char classes are functionally equivalent)
(?:[\x21-\x39\x3b-\x3f\x41-\x7e]+(?::[!-9;-?A-~]+)?@)?
(?#Next, let's match the domain [with support for