Replace occurrences of on_before_accelerator_backend_setup_called with setup hook

[krishnakalyan3]

What does this PR do?

Part-1/2 #11559

Does your PR introduce any breaking changes? If yes, please list them.

Before submitting

• Was this discussed/approved via a GitHub issue? (not for typos and docs)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure your PR does only one thing, instead of bundling different changes together?
• Did you make sure to update the documentation with your changes? (if necessary)
• Did you write any new necessary tests? (not for typos and docs)
• Did you verify new and existing tests pass locally with your changes?
• Did you list all the breaking changes introduced by this pull request?
• Did you update the CHANGELOG? (not for typos, docs, test updates, or internal minor changes/refactorings)

PR review

Anyone in the community is welcome to review the PR.
Before you start reviewing make sure you have read Review guidelines. In short, see the following bullet-list:

• Is this pull request ready for review? (if not, please submit in draft mode)
• Check that all items from Before submitting are resolved
• Make sure the title is self-explanatory and the description concisely explains the PR
• Add labels and milestones (and optionally projects) to the PR so it can be classified

Did you have fun?

Make sure you had fun coding 🙃

[ananthsub]

Thanks for working on this @krishnakalyan3

I'd make this into 2 PRs:

1. Transition all Lightning callbacks to use setup instead of on_before_accelerator_backend_setup. These callsites are shared in the initial issue
2. Mark the callback hook as deprecated (adding to the config validator, change the docstring of the hook to reflect it's deprecated, etc)

[ananthsub]

This needs to be updated too: https://github.com/PyTorchLightning/pytorch-lightning/blob/76c23f34b889fdce3351d1b1c2f657d52ff95bb2/tests/callbacks/test_stochastic_weight_avg.py#L236-L241

[krishnakalyan3]

Since this is a minor change do I need to update the change logs?.

[daniellepintz]

A few comments:

1. It looks like you are missing references in two tests: test_swa_deepcopy and test_deepspeed_assert_config_zero_offload_disabled
2. no need to update the changelog for this, but in the next PR yes
3. please update the title and description of this PR. this PR no longer fixes the issue directly, that will be the next PR

[krishnakalyan3]

@daniellepintz Let me know if the new changes look good.

[krishnakalyan3]

@daniellepintz let me know if this looks better.

[daniellepintz]

LGTM! Please fix the lint errors. You can check lint locally by running pre-commit (https://pre-commit.com/)

[krishnakalyan3]

@awaelchli let me know if the new changes look okay?.

[krishnakalyan3]

@daniellepintz

Looks like the pre-commit messages are picking up this from this signature def setup(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -> None:

Any suggestions on how to resolve this?

tests/strategies/test_deepspeed_strategy.py:409: [F821] undefined name 'pl'
tests/strategies/test_deepspeed_strategy.py:409: [F821] undefined name 'pl'
tests/callbacks/test_finetuning_callback.py:271: [F821] undefined name 'pl'
tests/callbacks/test_finetuning_callback.py:271: [F821] undefined name 'pl'
tests/callbacks/test_stochastic_weight_avg.py:236: [F821] undefined name 'pl'
tests/callbacks/test_stochastic_weight_avg.py:236: [F821] undefined name 'pl'

[awaelchli]

add import pytorch_lightning as pl
:)

[krishnakalyan3]

@rohitgr7 since stage is not referenced anywhere don't we have to initialize it somewhere as a global or a local variable?. In general, do we prefer typecasting the code for example trainer: "pl.Trainer" or as you suggested?.

[rohitgr7]

@rohitgr7 since stage is not referenced anywhere don't we have to initialize it somewhere as a global or a local variable?. In general, do we prefer typecasting the code for example trainer: "pl.Trainer" or as you suggested?.

@krishnakalyan3 stage will be set up trainer and passed to the callback's setup internally.
for tests, typing isn't required.