Changing the Python Language#

On occasion people come up with an idea on how to change or improve Python as a programming language. This document is meant to explain exactly what changes have a reasonable chance of being considered and what the process is to propose changes to the language.

What Qualifies#

First and foremost, it must be understood that changes to the Python programming language are difficult to make. When the language changes, every Python programmer already in existence and all Python programmers to come will end up eventually learning about the change you want to propose. Books will need updating, code will be changed, and a new way to do things will need to be learned. Changes to the Python programming language are never taken lightly.

Because of the seriousness that language changes carry, any change must be beneficial to a large proportion of Python users. If the change only benefits a small percentage of Python developers then the change will not be made. A good way to see if your idea would work for a large portion of the Python community is to ask in the Ideas Discourse category. You can also go through Python’s stdlib and find examples of code which would benefit from your proposed change (which helps communicate the usefulness of your change to others). For further guidance, see Suggesting new features and language changes.

Your proposed change also needs to be Pythonic. While only the Steering Council can truly classify something as Pythonic, you can read the Zen of Python for guidance.

Suggesting new features and language changes#

The Ideas Discourse category is specifically intended for discussion of new features and language changes. Please don’t be disappointed if your idea isn’t met with universal approval: as the long list of Withdrawn and Rejected PEPs in the PEP Index attests, and as befits a reasonably mature programming language, getting significant changes into Python isn’t a simple task.

If the idea is reasonable, someone will suggest posting it as a feature request on the issue tracker, or, for larger changes, writing it up as PEP following the PEP Process.

Sometimes core developers will differ in opinion, or merely be collectively unconvinced. When there isn’t an obvious victor, then the Status Quo Wins a Stalemate.

For some examples on language changes that were accepted, see Justifying Python Language Changes.

PEP Process#

Once you are certain you have a language change proposal which will appeal to the general Python community, you can begin the PEP process to officially propose the change. See PEP 1 for information on PEPs and the PEP process, and the PEP Index for examples.

If the PEP is accepted, then your proposed language change will be introduced in the next release of Python. Otherwise, your PEP will be recorded as rejected along with an explanation, to inform others who may propose a similar language change in the future.