Annotate return type of DiffusionPipeline.from_pretrained as Self | None

[gabayben]

DiffusionPipeline.from_pretrained returns Any | None. Return type should be explicitly annotated as Self | None.

[hlky]

Hi @gabayben. Thanks for raising this, I always add a type hint on instantiation as a workaround so it will be great to fix this.

from diffusers import FluxPipeline

pipeline: FluxPipeline = FluxPipeline.from_pretrained("")

Without we get this

from diffusers import FluxPipeline

pipeline = FluxPipeline.from_pretrained("")

(variable) pipeline: AuraFlowPipeline | ... | Any

With the change

(variable) pipeline: FluxPipeline

It looks like we can just add -> Self because from_pretrained should raise in all failure situations and never return None. Would you like to open a PR with the fix?

cc @yiyixuxu