GitLab

* Fix flake8 F401 '...' imported but unused

* One more F403

Restore `is_modelcards_available` in `.utils`.

Otherwise attempting to import `hub_utils` (in training scripts, for
example), fails.

This was removed during the refactor in df90f0ce.

* Add is_<framework>_available, refactor import utils

* deps

* quality

* test LMS with LDM

* test LMS with LDM

* Interchangeable sigma and timestep. Added dummy objects

* Debug

* cuda generator

* Fix derivatives

* Update tests

* Rename Lms->LMS