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uv has a feature where you can put a magic comment at the top of a script and it will pull all the dependencies into its central store when you do “uv run …”. And then it makes a special venv too I think? That part’s cloudier.

https://docs.astral.sh/uv/guides/scripts/

Makes it a snap to have a one file python script without having to explicitly pip install requests or whatever into a venv.



Example usage for those who haven't seen it yet:

  #!/usr/bin/env -S uv run --script
  #
  # /// script
  # requires-python = ">=3.12"
  # dependencies = ["httpx"]
  # ///
  
  import httpx
  
  print(httpx.get("https://example.com"))


> dependencies = ["httpx"]

I heavily recommend writing a known working version in there, i.e. `"httpx~=0.27.2"`, which, in the best case, would allow fixes and security patches (e.g. when httpx 0.27.3 releases), and, in the worst case, would let you change to `~=` to `==` in case httpx manages to break the backwards compatibility with a patch release.

And, of course, always use `if __name__ == "__main__":`, so that you can e.g. run an import check and doctests and stuff in it.


Import checks and doctests you can run before any script code anyway, and exit() if needed. The advantage of `if __name__ == "__main__":`, is that you can import the script as module on other code, as in that case __name__ will not be __main__.


That is amazing! I might use this instead of bash for some scripts.

I could imagine a Python wrapper script that parses the Python for import statements, then prepends these comments and passes it off to uv. Basically automating the process.




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