second note that is that you extract keys in `each_key` and then again lookup in hash, so for me more logic operation is to have both. The third note is that string is concanated with `+` not `.` as in perl. so something like
```
  need_sssd.each_pair do |key, needed|
     pkg = "sssd-#{key}"
     if needed && !Package.Installed(pkg) && Package.Available(pkg)
       to_install << pkg
     end
  end
```