Export/import user-defined dashboards

[Rub_moy]

Hi everyone,
The project i was working in got deprioritized. That work includes a explore in a development branch and dashboards. Since it's not deployed in production, the objects in my dashboard appear as errors while checking content validator.
What I want to achieve is to download those user-defined dashboards so the errors in content validator don't appear and, in the future, upload them again in my folder.
I've tried to create my dashboard as LookML Dashboard but I haven't been able to make it work.
Is there any way to simply export/import user-defined dashboards?

Thanks!