PyData London
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pydatalondon.bsky.social
PyData London
@pydatalondon.bsky.social
https://london.pydata.org

We run a monthly meetup and host the annual PyData London conference. PyData is an educational program of NumFOCUS, helping our community share ideas and learn from each other.

https://www.meetup.com/PyData-London-Meetup/
Find pytest-fixture-fixture on GitHub and install via pip or uv

github.com/fferegrino/p...
November 4, 2025 at 8:42 PM
It works with CV, JSON, JSONL and YAML,
has custom deserialisation, many (many!) out of the box fixtures, and even parameterisation.
November 4, 2025 at 8:37 PM
Pytest fixtures great but are slightly strange things. They feel a bit too much like magic sometimes.

@feregri.no solution is pytest-fixture-fixture (really!)

Fixtures, for fixtures. Handy fixtures to access your test fixtures from your pytest tests.
November 4, 2025 at 8:29 PM
Data-driven testing is an approach where test logic stays the same, but the input data and expected outputs come from external sources.

Here’s a Pytest example.
November 4, 2025 at 8:24 PM
Agents mean we can store data collected in the agent state and use that to feel more comfortable in what they predict vs a single (overconfident) LLM.

But don’t add AI tools if you don’t have to! Deterministic code is simpler and more reliable.
November 4, 2025 at 7:45 PM
There are many frameworks for creating agents but Geir is a fan of @hf.co smolagents. It’s simple to use and powerful enough for production.
November 4, 2025 at 7:41 PM
We’re entering the ALL CAPS era of doctstrings—because they end up in system prompts.
November 4, 2025 at 7:31 PM
Just asking an LLM to predict which team will win doesn’t work that well. It misinterprets data and doesn’t have enough domain knowledge to build trust and consistency.
November 4, 2025 at 7:28 PM
From small beginnings to great things! @emlynclay.bsky.social tells us the history of PyData London.
October 7, 2025 at 6:28 PM