Claude Sonnet 4.5 and Claude Agent SDK

• * Python 3.14*
• * Free-threaded Python Library Compatibility Checker*
• * Claude Sonnet 4.5*
• * Python 3.15 will get Explicit lazy imports*
• Extras
• Joke

About the show

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Brian #1: Python 3.14

• Released on Oct 7
• What’s new in Python 3.14
• Just a few of the changes
  • PEP 750: Template string literals
  • PEP 758: Allow except and except* expressions without brackets
  • Improved error messages
  • Default interactive shell now
    • highlights Python syntax
    • supports auto-completion
  • argparse
    • better support for python -m module
    • has a new suggest_on_error parameter for “maybe you meant …” support
  • python -m calendar now highlights today’s date
• Plus so much more

Michael #2: Free-threaded Python Library Compatibility Checker

• by Donghee Na
• App checks compatibility of top PyPI libraries with CPython 3.13t and 3.14t, helping developers understand how the Python ecosystem adapts to upcoming Python versions.
• It’s still pretty red, let’s get in the game everyone!

Michael #3: Claude Sonnet 4.5

• Top programming model (even above Opus 4.1)
• Shows large improvements in reducing concerning behaviors like sycophancy, deception, power-seeking, and the tendency to encourage delusional thinking
• Anthropic is releasing the Claude Agent SDK, the same infrastructure that powers Claude Code, making it available for developers to build their own agents, along with major upgrades including checkpoints, a VS Code extension, and new context editing features
• And Claude Sonnet 4.5 is available in PyCharm too.

Brian #4: Python 3.15 will get Explicit lazy imports

• Discussion on discuss.python.org

• This PEP introduces syntax for lazy imports as an explicit language feature:

  lazy import json
  lazy from json import dumps
  

• BTW, lazy loading in fixtures is a super easy way to speed up test startup times.

Extras

Brian:

• Music video made in Python - from Patrick of the band “Friends in Real Life”
  • source code: https://gitlab.com/low-capacity-music/r9-legends/

Michael:

• New article: Thanks AI
• Lots of updates for content-types
• Dramatically improved search on Python Bytes (example: https://pythonbytes.fm/search?q=wheel use the filter toggle to see top hits)
• Talk Python in Production is out and for sale

Joke: You do estimates?