Perl vs. python vs. Lua?

[Dom Latter]

Hi,

we have been using the exec module with version 2 to run an external PHP
script that (for example) assigns a VLAN depending on the user's
location [1] - this is done post-auth.

We have migrated to freeradius version 3.

I note from
http://networkradius.com/doc/3.0.10/raddb/mods-available/exec.html
that
"The exec module may look like it works for one or two tests, but in a
  live situation it can cause the server to become unresponsive under
  load. The perl module is recommended for general-purpose computing."

Now if I had read that four years ago I'd not have gone down the
exec route... anyway.

So it seems to me we need to rewrite the exec module using one
of the scripting modules.

So I am wondering how the python module compares to the perl module.

I found and read a great post from Herwin Weststrate 
<herwin at quarantainenet.nl> from November 2016 that explains
some of the differences.

I'd rather use python than perl, all else being equal.

Lua is an outlier of an option.

Any thoughts?

Apologies if any of the above is unclear.

[] which we get from the access-point identifier string.