Sync itertools-in-python3 with the updated tutorial

[realpython-bot]

Companion sync for the maintenance update of Python itertools By Example.

What changed

• itertools-in-python3/README.md: the "Note" about which interpreter to invoke pointed at python3.6 / python36. The tutorial's dependencies field moved from python==3.6 (end of life since 2021-12-23) to python==3.14 in this maintenance pass, so the README now names python3.14 / python314.

sp500.py and swimmers.py needed no changes: they already match the article's updated full listings (the p <= zdp / p > zdp filterfalse() predicates that the article's inline snippets were fixed to use, double-quoted strings, and csv.DictReader rows treated as plain dictionaries). There is no requirements.txt in this folder — both scripts are standard library only — so there were no pins to move.

How it was verified

• uv run --python 3.14 --no-project python sp500.py → Max gain: 11.58% on 2008-10-13 / Max loss: -20.47% on 1987-10-19 / Longest growth streak: 14 days (1971-03-26 to 1971-04-15), byte-for-byte the output the README and the article print.
• uv run --python 3.14 --no-project python swimmers.py → the eight relay-team lines exactly as shown in the README and the article.
• uvx ruff@0.14.1 format --check itertools-in-python3 → 2 files already formatted.
• uvx ruff@0.14.1 check itertools-in-python3 → All checks passed!.

Links

• Article draft (admin): https://realpython.com/pbjt/blog/post/2399/change/
• Article draft (preview): https://realpython.com/python-itertools-update/
• Maintenance card: https://trello.com/c/KBrpVVwD