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The best thing is to contact them to get their stuff. Let them know they have a certain time to get it (2 weeks is more than reasonable in most cases), or its going to get tossed. If they don't make the time/effort to get their things after that point, pitch it (or keep it if you can use it).
Just throw it away. Unless it's like something you're going to end up on judge Judy over just get rid of it.
I would give them back
If it's stuff like you're describing I would just toss it. But if there are items such as clothing, books, phone chargers etc. I would stick them in a box and tell them to come pick up their shit.
Contact her and give it back
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