Description

methane

opened on Apr 27, 2025

Issue body actions

Discussion: https://discuss.python.org/t/deprecating-codecs-open/88135/

codecs.open() is used a lot because it was recommended in Python 2.
But open() (or io.open()) is recommended since Python 3.

It is a time to deprecate codecs.open().
Since it is still widely used, we won't schedule its removal.

Linked PRs

• gh-133036: Deprecate codecs.open #133038

Activity

1. methane

   added

   stdlibStandard Library Python modules in the Lib/ directoryStandard Library Python modules in the Lib/ directory

   on Apr 27, 2025
2. methane

   self-assigned this

   on Apr 27, 2025
3. methane

   added this to Codecs and encodings issueson Apr 27, 2025
4. methane

   added a commit that references this issue on Apr 27, 2025

   pythongh-133036: deprecate codecs.open

   655759b
5. picnixz

   added

   type-featureA feature request or enhancementA feature request or enhancement

   on Apr 27, 2025
6. methane

   added a commit that references this issue on Apr 30, 2025

   gh-133036: Deprecate codecs.open (#133038)

   4e294f6
7. hugovk

   closed this as completedon Apr 30, 2025
8. github-project-automation

   moved this to Done in Codecs and encodings issueson Apr 30, 2025
9. ngoldbaum commented on Aug 7, 2025

   

   ngoldbaum

   on Aug 7, 2025

   Contributor

   More actions

   I don't know if this deserves a better clarification in the deprecation notice, but I hit a corner case that took me a few minutes to understand today. Perhaps commenting here will help someone else.

   I tried replacing codecs.open with open in a spot in pandas and hit this error:

   >               with open(as_json, "wb", encoding="utf8") as f:
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   E               ValueError: binary mode doesn't take an encoding argument
   

   I fixed it by replacing "wb" with "w". It seems codecs.open is a little more permissive here than open.

Issue actions