Is this a real plugin yet, and if, where can it be found?

If you managed to compile it in then you can call it in expression using following form:

python::exec( python_modulename, python_func_name, arg)

All args are mandatory. And you should set PYTHONPATH to where your module is located, before executing lcd4linux.

Example:

expression python::exec('mypy','echo',LCD::GPI(1) . ',ggg ,' . tick)

PS: There is linking errors when plugin tries to load standard python modules (for example: time.time()).