PEP Talk

If you use Python, chances are you've heard of PEP 8, the Python style guide.

But do you know what PEPs really are? PEPs are more than just a style guide. A PEP stands for Python Enhancement Proposal. It's a proposal documentation for when you want to change the Python programming language in a big way, for example when you want to change the syntax of Python. Think of the addition of f-strings, the walrus operator, or the ExceptionGroup, those changes all started with a PEP.

Let's have a PEP talk, where you can learn about the PEP process, what needs a PEP and what doesn't, and how you as community members can take part.

Transcript

1. PEP Talk
   b y M a r i a t t a
   North Bay Python 2023
   https://fosstodon.org/@mariatta
   
   
   

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2. PEP 8: Style Guide for Python Code
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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3. PEP 8: Style Guide for Python Code
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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4. PEP 8: Style Guide for Python Code
   “This document gives coding conventions for the Python code
   comprising the standard library in the main Python
   distribution.”
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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5. PEP != Style Guide Documentation
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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6. PEP != Style Guide Documentation
   So … what’s a PEP?
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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7. PEP 1: PEP Purpose and Guidelines
   “PEP stands for Python Enhancement Proposal.
   A PEP is a design document providing information to the Python
   community, or describing a new feature or its processes or
   environment. The PEP should provide a concise technical
   specification of the feature and a rationale for the feature.”
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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8. What needs a PEP?
   What doesn’t need a PEP?
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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9. Making Changes to Python
   Bugs, crashes, docs issues, feature requests, etc
   File them on GitHub: https://github.com/python/cpython
   North Bay Python 2023
   PEP Talk by Mariatta
   https://fosstodon.org/@mariatta
   
   
   

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10. Making Changes to Python
    Changes to the language itself, grammar, syntax, adding a
    new module, new keyword, new operator: PEP required
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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11. Example PEPs
    PEP 498: Literal String Interpolation (f-strings)
    PEP 572: Assignment Expressions (the “walrus” operator)
    PEP 654: Exception Group and excepts
    PEP 492: Coroutines with async and await
    Typing PEPs: PEP 482, 483, 484, 526, 561, etc
    Packaging PEPs
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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12. Governance PEPs
    PEP 13: Python Language Governance
    PEP 609: PyPA Governance
    PEP 8000: Python Language Governance Proposal
    Overview
    PEP 8016: The Steering Council Model
    PEP 810x: Steering Council elections
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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13. Core Workflow and Infrastructure PEPs
    PEP 512: Migrating from hg.python.org to GitHub
    PEP 581: Using GitHub Issues for Python
    PEP 545: Python Documentation Translations
    PEP 676: PEP Infrastructure Process
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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14. Release PEPs
    PEP 719: Python 3.13 Release Schedule
    PEP 693: Python 3.12 Release Schedule
    PEP 664: Python 3.11 Release Schedule
    …
    Also at https://devguide.python.org/versions/#versions
    
    
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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15. PEP Lifecycle
    Start with an idea for Python
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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16. PEP Lifecycle
    Start with an idea for Python
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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17. problem
    PEP Lifecycle
    Start with an idea for Python
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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18. PEP Lifecycle
    Discuss your idea problem with core devs and contributors
    - open an issue on GitHub1
    - start a thread on Python Discourse2
    - discuss at Python Language Summit at PyCon US
    North Bay Python 2023
    PEP Talk by Mariatta
    1: https://github.com/python/cpython
    2: https://discuss.python.org/c/core-dev/23
    https://fosstodon.org/@mariatta
    
    
    

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19. PEP Lifecycle
    If it can’t be solved by third party library on PyPI,
    If it requires changes to the language itself
    You’ll need a PEP (and a PEP sponsor)
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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20. PEP Lifecycle
    Write the PEP
    Champion your idea solution to your problem
    Document discussions, questions, pushbacks, reasonings,
    etc
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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21. PEP Lifecycle
    Submit the PEP for Steering Council’s review
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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22. PEP Lifecycle
    PEP accepted? Congrats!!! 🎉
    It can be included in Python
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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23. PEP Lifecycle
    PEP is a proposal doc, not feature documentation
    The feature should be documented at docs.python.org
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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24. PEP Lifecycle
    Could take months, and in some cases: years
    PEP 525 (async generator): 2 months
    PEP 557 (data classes): 9 months
    PEP 572 (the walrus): 18 months
    PEP 517 (build system/Packaging): 2 years
    Most time are spent in discussions and consensus building
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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25. Your Role
    PEPs will affect how you use Python (things could break)
    Python core devs have blind spots: Your input matters
    Bring up your concerns during PEP discussion period
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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26. Case study:
    PEP 563 (2017)
    vs
    PEP 649, Pydantic, FastAPI
    (2021)
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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27. Case study:
    PEP 563 (2017)
    vs
    PEP 649, Pydantic, FastAPI
    (2021)
    North Bay Python 2023
    PEP Talk by Mariatta
    P.S. PEP 649 was accepted May 2023
    https://fosstodon.org/@mariatta
    
    
    

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28. Your Role
    Keep up to date with PEPs!
    New PEPs are announced on Discourse:
    discuss.python.org/c/peps
    Test your code against Python pre-releases: (alpha, beta,
    release candidate): check the Release Schedule
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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29. “The steering council shall work to: …
    Seek consensus among contributors and the core team…”,
    PEP 8016
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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30. “A PEP is a design document providing information to the
    Python community”,
    PEP 1
    North Bay Python 2023
    PEP Talk by Mariatta
    https://fosstodon.org/@mariatta
    
    
    

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31. Thank You
    North Bay Python 2023
    P E P Ta l k
    b y M a r i a t t a
    https://fosstodon.org/@mariatta
    

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