This should make Python updates easier.

MAINT use variables for Python version rather than hardcoding it. This should make Python updates easier.

*.gen.*
_build
build
.artifacts
.docker_home
.mypy_cache
emsdk
cpython
.vscode
.pytest_cache
.clang-format
packages/CLAPACK/make.inc

*.gen.*
_build
build
.artifacts
.docker_home
.mypy_cache
emsdk
cpython
.vscode
.pytest_cache
.clang-format
packages/CLAPACK/make.inc
