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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Document in guide stdin usage
alllll the easter eggs can do as well, but declined to keep consistent
with the other examples 😆
Additions to https://github.com/astral-sh/uv/pull/6481
```bash
$ uv run - <<EOF
import antigravity
EOF
```
## Test Plan
<!-- How was it tested? -->
https://github.com/astral-sh/uv/pull/6519#issuecomment-2307371063 new PR
Billy Doyle
3f147eeb06