Long:
For lua there is two "types" of shared libraries you can want to load:
1) lua modules.
It is how you load your mentioned module in python.
They should contain `luaopen_<LIBNAME>` entry point (function), which is
called by interpreter on load.
2) FFI.
For example, LuaJIT allows you to load (like `dl()`) any shared library, and
call functions from there, like you would do when writing code in C.
AFAIRC, there was a module providing something like that for PUC-Rio Lua too.