These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.77 s (backtrack: 0/20).

[ebuild  N     ] virtual/fortran-0-r1::gentoo  USE="openmp" 0 KiB
[ebuild  N     ] sci-libs/openblas-0.3.34::gentoo  USE="openmp -cpudetection -index64 -pthread -relapack -test" 24734 KiB
[ebuild  NS    ] dev-lang/python-3.12.15:3.12::gentoo [3.13.12:3.13::gentoo, 3.14.3:3.14::gentoo] USE="ensurepip gdbm ncurses pgo readline sqlite ssl -bluetooth -debug -examples -libedit -test -tk -valgrind -verify-sig (-jit%) (-tail-call-interp%)" LLVM_SLOT="(-19%*)" 20356 KiB
[ebuild  N     ] sci-libs/lapack-3.12.1-r2::gentoo  USE="deprecated flexiblas lapacke -doc -eselect-ldso -index64 -test" 7879 KiB
[ebuild  N     ] sci-libs/flexiblas-3.5.0::gentoo  USE="openblas openmp system-blas -blis -index64 -mkl -tbb -test" 80741 KiB
[ebuild  N     ] sci-libs/blas-lapack-aux-wrapper-6::gentoo  USE="-index64 -test" 10 KiB
[ebuild  N     ] virtual/blas-3.8-r1::gentoo  USE="flexiblas -eselect-ldso -index64" 0 KiB
[ebuild  N     ] virtual/lapack-3.10-r1::gentoo  USE="flexiblas -eselect-ldso -index64" 0 KiB
[ebuild  N     ] sci-mathematics/petsc-3.22.2::gentoo  USE="X examples threads -afterimage -boost -complex-scalars -debug -fftw -fortran -hdf5 -hypre -int64 -metis -mpi -mumps -scotch -superlu" 16361 KiB

Total: 9 packages (8 new, 1 in new slot), Size of downloads: 150077 KiB