Custom sampler in TrainingArguments
Author: romitjain
Pull request: yes

# What does this PR do?

This PR adds a new flag to the `TrainingArguments` which enables the user to pass a custom sampler function. This is useful in cases when the user wants to maintain the order of the dataset provided (curriculum learning) or other cases where they want to use a custom sampler for the dataloader.

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Fixes # (issue)

#26802 

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Comments:
View the CircleCI Test Summary for this PR:

https://huggingface.co/spaces/transformers-community/circle-ci-viz?pr=43318&sha=ea6bea

cc @SunMarc, but the original issue is quite old. Did you check if this is still valid? A lot of people run code agents to "fix issues" but they often find older issues that are no longer relevant.

We do have this PR that is ready to be merged so I will close this one ! https://github.com/huggingface/transformers/pull/43138

Thanks for PR nevertheless @romitjain 

Thanks @SunMarc 
I will wait for that PR to get merged.