Does she engage you in conversation at all? If so, is it about the books/dvd's you're checking out at the library? Heck, even if not - lead the conversation there. ie whether she says hi or you say hi, let her know you're checking out the dvd titles to see if there's anything particularly good to watch. Maybe she'll make some recommendations, or comment on your selection.. but regardless, if you can get chatting about movies at all - then you can bring up that there's a show playing currently you'd like to go see & then just flat out ask her if she'd care to check it out with you. If you're feeling particularly bold, you could use the word "date," so as for her not to confuse your intentions for a "just friends," invite. Heck, even if your conversation is about books, or the whether, or the local sports team, or whatever, once you're engaged in some meaningful chit-chat you can steer the conversation over to the movie you'd like to take her to. "Yeah, these books (or insert topic) are great, but I'd like to switch things up and catch ____ movie this Friday.. would you like to join me?" So many ways to transition a conversation over to what you want. It depends on how it plays out in real life as to how you'll phrase it exactly. You don't want to pick one line and then try to rigidly rehearse it and make it work in any scenario, because chances are there won't be the perfect situation for your line to sound fluid and real vs. fake and rehearsed.. so, be flexible, but get to the point you want to make, ask your question, get your answer & then move forward either planning a date or knowing she's not interested.
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for supporting trump. Because doing so is deplorable.