Websockets in Python script closing when launched from Arduino (not from shell)

¡Hello everybody!
I'm working on a new project (or an update of a previous one) and I am having a very weird error.
OK, I am using Websockets in Python to serve info to some clients (6 cellphones) while lightning some LEDs.
We get a hashtag from Twitter, update a client through websockets and launch some Arduino code.

Here comes the weirdness: when I run the python script from shell trhough SSH the script works as expected all the tim and I can see the changes on the clients and Serial Monitor reads the Bridge perfectly.
Buuuuut, when I launch the python script from Arduino (as I did previously with another python script) it starts and works fine during... 2 minutes. After that time, websockets get closed, I get no error (Serial Monitor in Arduino still prints right results), script keeps open but don't get any update in any client.

I have tried running process with run, runAsync , shell, shellAsync, changed permissions, check shebang...
I know I can run the script on startup but this has some drawbacks attending to error control.

Any idea?

¡Thank you very much!