2330 Enhance all_gather APIs for regular PyTorch programs

[Nic-Ma]

Fixes #2330 .

basic warnings for #2335

Description

This PR adjusted the evenly_divisible_all_gather and string_list_all_gather APIs to support regular PyTorch programs.
Thanks for @vfdev-5 's help, referring to the basic idea of ignite all_gather(string).
And resolved the max_length=1024 issue of ignite v0.4.4.

Status

Ready

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).
• Breaking change (fix or new feature that would cause existing functionality to change).
• New tests added to cover the changes.
• Integration tests passed locally by running ./runtests.sh -f -u --net --coverage.
• Quick tests passed locally by running ./runtests.sh --quick --unittests.
• In-line docstrings updated.
• Documentation updated, tested make html command in the docs/ folder.

[Nic-Ma]

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[Nic-Ma]

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[Nic-Ma]

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[wyli]

thanks, please see some comments inline. there are some utility functions moved from monai.handlers.utils to monai.utils, we need a deprecation method for this type of change as well @ericspod, any suggestions for this PR or shall we have another PR for the deprecating module?

[Nic-Ma]

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[Nic-Ma]

Hi @wyli ,

Thanks for your review and comments.
For this kind of deprecated API, maybe I should not delete the previous implementation, just add a warning in the function:

warnings.warn("evenly_divisible_all_gather had been moved to monai.utils module, will deprecate this API in MONAI v0.7.", DeprecationWarning)

Or any other suggestions? Or some overall advanced method to handle it?

Thanks.

[ericspod]

For now you can add the warning but I'm going to have a PR shortly on a more involved mechanism.

[Nic-Ma]

Hi @ericspod ,

Sounds good!
I added the warning message to the deprecated APIs.

Thanks.

[Nic-Ma]

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[wyli]

thanks, this PR also had a workaround for #2335