Two different versions of Python present in the same spec

[dipietrantonio]

I was trying to build a specific version of wsclean. The recipe has got depends_on("python@:3.10") so I would expect the 3.9.15 version to be picked up.

cdipietrantonio@nid001774:~> spack spec --reuse wsclean@3.1 +everybeam | grep python@
[^]          ^python@3.11.6%gcc@12.2.0 cflags="-O3" cppflags="-O3" cxxflags="-O3" fflags="-O3 -fallow-argument-mismatch" +bz2+crypt+ctypes+dbm~debug+libxml2+lzma~nis+optimizations+pic+pyexpat+pythoncmd+readline+shared+sqlite3~ssl~tkinter+uuid+zlib build_system=generic patches=13fa8bf,b0615b2,ebdca64,f2fd060 arch=linux-sles15-zen3
[^]      ^python@3.9.15%gcc@12.2.0 cflags="-O3" cppflags="-O3" cxxflags="-O3" fflags="-O3 -fallow-argument-mismatch" +bz2+crypt+ctypes+dbm~debug+libxml2+lzma~nis+optimizations+pic+pyexpat+pythoncmd+readline+shared+sqlite3~ssl~tkinter+uuid+zlib build_system=generic patches=0d98e93,4c24573,ebdca64,f2fd060 arch=linux-sles15-zen3

Without the --reuse flag I get this

cdipietrantonio@nid001774:~> spack spec wsclean@3.1 +everybeam | grep python@
==> Warning: using "curl@7.79.1" which is a deprecated version
==> Warning: using "openssl@1.1.1" which is a deprecated version
 -       ^python@3.10.13%gcc@12.2.0 cflags="-O3" cppflags="-O3" cxxflags="-O3" fflags="-O3 -fallow-argument-mismatch" +bz2+crypt+ctypes+dbm~debug+libxml2+lzma~nis+optimizations+pic+pyexpat+pythoncmd+readline+shared+sqlite3~ssl~tkinter+uuid+zlib build_system=generic patches=0d98e93,7d40923,ebdca64,f2fd060 arch=linux-sles15-zen3

it chose a version that is not installed over the pre-installed python@3.9.15.