Now I found this text on the internet
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Text :
H: There are two kinds of women: high maintenance and low maintenance.
S: And Ingrid Bergman is low maintenance?
H: An L.M. Definitely.
S: Which one am I?
H: You're the worst kind. You're high maintenance, but you think you're low maintenance.
S: I don't see that.
H: You don't see that? (He mimicks her typical ordering procedure) 'Waiter, I'll begin with the house salad, but I don't want the regular dressing. I'll have the balsamic vinegar and oil, but on the side, and then the salmon with the mustard sauce, but I want the mustard sauce on the side.' 'On the side' is a very big thing for you.
S: Well, I just want it the way I want it.
H: I know, high maintenance. (S sighs after Bogart says the final line of the film, when the two characters walk off into the fog-shrouded airport: 'Louis, I think this is the beginning of a beautiful friendship.') Ooh. Best last line of a movie, ever.
Hope I eliminated all hints to the name of that movie. 8)