Validate models are loadable
# 🚀 Feature request

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Validating models uploaded to the hub in some way

## Motivation

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I so far only loaded t5-small models en masse (or generally that are not the pretrained version). I have found a third of the models are unloadable!
Followed this discussion: https://discuss.huggingface.co/t/cant-download-some-models-although-they-are-in-the-hub/13944
## Your contribution

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I am not sure, I don't know how the code to the hub itself works, I think the fix is not too complicated for others that do.
I suggest a loading code must be added to the uploading to the hub (with the default of autoWhatever.from_pretrained() or even not adding and always assuming that). Then if the users' own code fails when they try to upload, then you say upload failed unloadable. In that way there won't be models where they have a description, but actually, the files are not there, or they miss some of the files needed to load.
Moreover, this would make for an easy way for people to start, loading the model would be known (again, may be just skipped if assumed the default from_pretrained is always this way).
This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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