They claim that, but I don't see how it could possibly be true, based on the cast listing at https://www.imdb.com/title/tt0056172/fullcredits : apart from an uncredited nurse (Barbara Cole) it seems like a screenplay calculated to make Ms Bechdel sad.
True — I ought to have considered that, for I know the book Seven Pillars of Wisdom has in supertext some passages that (if they made it at all) are probably only referred to in the movie as subtext. mea culpa
(Consider the period)