Improve performance by replacing PyTuple_Pack with PyTuple_FromArray

[eendebakpt]

Feature or enhancement

Proposal:

The PyTuple_Pack method is relatively slow because it is a variadic function. For various cases (in particular tuples of size 1 and 2) we can replace PyTuple_Pack with PyTuple_FromArray (introduced in #111489)

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-140009: Improve performance of list_extend_dictitems by using PyTuple_FromArray #140010

[StanFromIreland]

I suggest not applying the easy label if a PR is already open, since these issues are often checked by new contributors, and there not much for them to do here otherwise.

[eendebakpt]

I suggest not applying the easy label if a PR is already open, since these issues are often checked by new contributors, and there not much for them to do here otherwise.

The open PR addresses only one occurrence of PyTuple_Pack, but there potentially more. All the cases for PyTuple_Pack(1, ...) are easy (although not all provide a meaningfull performance improvement), so good to pick up by new contributors.