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How about the digestive system?
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A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.

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This is a science community. We use the Dawkins definition of meme.
I got a T shaped cat tunnel. It's got two holes. I think. Topology can go suck a lemon
Still one hole unless there's isolated sections
Which is why I said SINGLE tunnel.