fix imports of OrderedDict from typing to collections

[ethanjyx]

Changes proposed in this pull request:

Remove any imports of OrderedDict from typing module.
OrderedDict is not included into typing until Python 3.7.2, at my company right now we are using Python 3.6.9 and this is causing issues for us.
Also OrderedDict from typing is deprecated later since Python 3.9. Reference: https://docs.python.org/3/library/typing.html#typing.OrderedDict.

So importing OrderedDict from typing is not a good idea, and we change that to import from collections here.

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[ethanjyx]

I had to change this to Mapping because with OrderedDict from collections I got TypeError: 'type' object is not subscriptable

[epwalsh]

Hmm, have you tried quoting OrderedDict? Like

Suggested change

	StateDictType = Union[Dict[str, torch.Tensor], Mapping[str, torch.Tensor]]
	StateDictType = Union[Dict[str, torch.Tensor], "OrderedDict[str, torch.Tensor]"]

[ethanjyx]

Sorry - haven't got time to respond and test. @epwalsh are you going to take this over? Saw you self-assigned.

[epwalsh]

Hey @ethanjyx, unfortunately we dropped support for 3.6 as of #5400.

[ethanjyx]

@epwalsh thanks for letting me know that, that's helpful.

But you still might want to consider doing this PR, since OrderedDict from typing is deprecated since Python 3.9 and this code will break.

[epwalsh]

Good point! Well if you'd like to finish it up I'm happy to reopen it then

[ethanjyx]

I'll finish it up in January. Pls reopen. Thanks

[ethanjyx]

@epwalsh looks like your suggested approach did not pass lint.. any ideas? not familiar with types within quotes

[dirkgr]

@ethanjyx, are you working on this again?

[ethanjyx]

@dirkgr this slipped through - do you have time to continue it?

[ethanjyx]

@epwalsh @dirkgr I believe I fixed this PR - just waiting the CI, can you pls approve the running workflows?

[dirkgr]

No problem. It turns out I don't have permission to fix the merge conflicts. Should be easy to resolve though.

[ethanjyx]

ping @epwalsh

[dirkgr]

You can run those checks locally:

make format
make flake8
make typecheck

It looks to me like there is just one import missing.

[ethanjyx]

@epwalsh can you kick the CI off? thanks

[epwalsh]

Hi @ethanjyx, you'll need to fix the merge conflicts before CI can run

[epwalsh]

Closing since this PR is stale and we don't officially support 3.6 anymore, anyway.