Add these to limited API:

• Py_PACK_FULL_VERSION(x, y, z, level, serial): pack a version number from components
  into the format used byPy_VERSION_HEX andPy_LIMITED_API.
  For example,Py_PACK_FULL_VERSION(3, 14, 0, 0xA, 1) evaluates to 0x030E00A1.

• Py_PACK_VERSION(x, y): shorthand forPy_PACK_FULL_VERSION(x, y, 0, 0, 0),
  useful because the first two version components often determine ABI
  compatibility.

These are primarily macros, but we will export library functions with the same names and functionality, for use in wrappers for non-C languages – for example, Python withctypes.

The functions takeint arguments and returnuint32_t. Inputs are masked (high bits are ignored).

C API WG decision:capi-workgroup/decisions#47

Linked PRs

• gh-128629: Add Py_PACK_VERSION and Py_PACK_FULL_VERSION #128630
• gh-128629: Add _Py_PACK_VERSION for CPython's own definitions #134247