quite/alot — comment on commit bd8ba8effb717ee50d0963d1f4ca7ea1a77d1f45
File:  line 0
By quite:

The only dict there is settings._header_order, and it is only caculated once, upon the first call to settings.get_header_order() (when it is found to be None).

I think it is rather efficient. Except for perhaps the

lines = [(k, v) for (k, v, x) in lines]

Which might be done in some better way?