Left a longer comment on the issue but to summarize I was a bit surprised to discover that just importing typing.ByteString didn't seem to create a DeprecationWarning in 3.13.

#118803 (comment)

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot s390x RHEL8 LTO 3.x (tier-3) has failed when building commit 530ddd3.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/567/builds/10135) and take a look at the build logs.
4. Check if the failure is related to this commit (530ddd3) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/567/builds/10135

Summary of the results of the build (if available):

==

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-rhel8-s390x.lto/build/Lib/contextlib.py", line 112, in __init__
    doc = getattr(func, "__doc__", None)
ValueError: flush of closed file
Warning -- Unraisable exception
Exception ignored while finalizing file <_io.BufferedWriter>:
Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-rhel8-s390x.lto/build/Lib/contextlib.py", line 112, in __init__
    doc = getattr(func, "__doc__", None)
ValueError: flush of closed file
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