Refactor version checking into a utility

[muellerzr]

Refactor version checking into a utility

What does this add?

This PR adds two new functions:

• compare_versions
• check_torch_version

Which checks a particular version, querying with a string of the comparitor (such as "<" or ">=" or "!=")

Why is it needed?

I was noticing we do a lot of checks with version.parse in the code, and we already had a versions submodule for getting the current torch version. As a result, it made sense to expand this utility further to have it check for all of our torch versions.

Also considering that most of them are comparing the torch version specifically, I added a check_torch_version which shorthands the query on the user.

What parts of the API does this impact?

User-facing:

Nothing

Internal structure:

Modifies all version checks to use compare_versions or check_torch_version

Basic Usage Example(s):

For checking a non-torch library:

from accelerate.utils import compare_versions
compare_versions("fastai", "<", "2.0.0")

For checking a torch version:

from accelerate.utils import check_torch_version
check_torch_version("<=", "1.10")

[sgugger]

Nice refactor!

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[sgugger]

Left some nits to the doc, but otherwise looks great! Thanks for working on this!