[Twisted-web] Authentication with twisted.web

[Paul Moore]

I want to build a web application which requires users to log on. I'm happy 
building the user authentication side of things, but I'm not sure how to get 
the site to require authentication. I'm looking for what I think is "Basic" 
authentication - the one that causes the browser to pop up an "enter username 
and password" dialog box. I know that I could design my own front page form, to 
allow the user to enter a username directly, but that's not what I want here.

Is this possible? (I'm sure it is, I just can't find what I should be looking 
for in the docs!)

Thanks,
Paul.