I totally agree with you. But I just know the basics of python: variables, print and arithmetic, nothing else. I'm studying by my self a bit more of python, but isn't still enough to make pieces of code and understand how it works. Maybe In a few months I will be able to do this and ask you again. Thank you guys and sorry.

Actually a I'm using instant print, but is not so good for what I need. Python is good option, but i just have some basic basic notions. Thanks.

No. What i have is subgroups inside each goup, but the subgroups also have differents name.

Jhosep I've tried it several times, and have figured out that this only works when I click on a particular layer within the group layer. When I do this, the function returns the name of the group layer to layer belongs.

Yes, i click. But nothing happens

Jhosep don't worry, I'm grateful for your help. I close the qgis and a i restart the computer and now in the title appear the return message "Group not found". So maybe the problem is relate to the if statment, what do you think?

Jhosep, i had the some problem again :(

Jhosep, I place inside the function and gives me an error when i load:"invalid syntax"

I load the function and I refresh the qgis composer and qgis project.

The label not update, just appears the expression text " [%func()%]" in the title.

Joseph I had the same problem again. I replace the words, but doesn't work