How do you limit an array subelement in Mongo?
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Let's say I have the following data model in Mongo:
    
    {
       _id: ...,
       name: "...",
       obj: {...},
       list: [ ... ],
    }

Now let's say, my `list` array is very long, and I don't want to grab the whole document every time. So I want to get `obj` and `name`, but only grab the last 5 elements in `list`. How do you do this with with Mongo? I'm using pymongo.