My criterion for delayed imports is that they're only worth it if the
majority of users of the module would benefit from it, otherwise you're
just moving latency around unpredictably.
mktime_tz is not used anywhere in the standard library and grep.app
indicates it's not got much use in the ecosystem either.
Distribution.files is not nearly as widely used as other
importlib.metadata APIs, so we defer the csv import.
Before:
```
λ hyperfine -w 8 './python -c "import importlib.metadata"'
Benchmark 1: ./python -c "import importlib.metadata"
Time (mean ± σ): 65.1 ms ± 0.5 ms [User: 55.3 ms, System: 9.8 ms]
Range (min … max): 64.4 ms … 66.4 ms 44 runs
```
After:
```
λ hyperfine -w 8 './python -c "import importlib.metadata"'
Benchmark 1: ./python -c "import importlib.metadata"
Time (mean ± σ): 62.0 ms ± 0.3 ms [User: 52.5 ms, System: 9.6 ms]
Range (min … max): 61.3 ms … 62.8 ms 46 runs
```
for about a 3ms saving with warm disk cache, maybe 7-11ms with cold disk
cache.
* Sync with importlib_metadata 7.0.0
* Add blurb
* Update docs to reflect changes.
* Link datamodel docs for object.__getitem__
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
* Add what's new for removed __getattr__
* Link datamodel docs for object.__getitem__
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
* Add exclamation point, as that seems to be used for other classes.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Confirmed with @jaraco that this indeed needs a fix.
A question that came up while I was digging into the code: I think `SelectableGroups` could similarly use `__slots__ = ()`, since its purpose seems only for convenience around `dict`, not to have attributes of its own.
Automerge-Triggered-By: GH:jaraco
* bpo-44893: Implement EntryPoint as simple class and deprecate tuple access in favor of attribute access. Syncs with importlib_metadata 4.8.1.
* Apply refactorings found in importlib_metadata 4.8.2.
* bpo-43926: Cleaner metadata with PEP 566 JSON support.
* Add blurb
* Add versionchanged and versionadded declarations for changes to metadata.
* Use descriptor for PEP 566
Jason R. Coombs
Adam Turner
Shantanu
Victor Stinner
Arie Bovenberg
Filipe Laíns
Barry Warsaw
Anthony Sottile