Allow remote code repo names to contain "."

[akasharidas]

What does this PR do?

When the repo path for a model containing custom code contains ., the code fails to import it correctly because . is interpreted by the Python import machinery as a module separator. This issue was reported in Transformers (huggingface/transformers#28919) and was fixed in huggingface/transformers#29175. The same issue exists in Diffusers, so this PR brings over that fix with minor changes to account for how Diffusers names the cache directory.

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Who can review?

@yiyixuxu @sayakpaul @asomoza

[sayakpaul]

Looks pretty good! Should we add a test for it here?

diffusers/tests/pipelines/test_pipelines.py

Line 1009 in c934720

class CustomPipelineTests(unittest.TestCase):

[sayakpaul]

Could we do:

def get_class_in_module(class_name, module_path, pretrained_model_name_or_path=None):

This will ensure the change is not backward breaking.

[akasharidas]

Thanks for the feedback, I've made the proposed change

[akasharidas]

Looks pretty good! Should we add a test for it here?

diffusers/tests/pipelines/test_pipelines.py

Line 1009 in c934720

class CustomPipelineTests(unittest.TestCase):

To test this we need a repo that both has a dot in the name and has custom remote code. Currently I'm testing it on a private repo. @sayakpaul could you help by creating a new repo on hf-internal-testing for this? You could just duplicate hf-internal-testing/tiny-sdxl-custom-all into something like hf-internal-testing/tiny-sdxl-custom-all-1.0 and then I can write a test similar to test_remote_auto_custom_pipe.

[akasharidas]

Added a test for it in tests/pipelines/test_pipelines.py. Currently it depends on this test repo in my account. Feel free to move it into hf-internal-testing.