[EZ] Pass seed to data sampler.

[EugenHotaj]

We currently hardcode zero. I assume this is not intentional.

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[RdoubleA]

Getting the seed from self.seed is risky, since we are using self.seed = training.set_seed() in our recipes, which will actually return a different seed on every rank. I am not sure if the sampler should have the same seed across ranks, but I imagine to ensure all ranks are not shuffling the data differently we would want the same seed. It would be better to set it from cfg.seed directly to keep the same data seed across all ranks.

Tagging @andrewkho for thoughts on setting the seed in DistributedSampler.

[EugenHotaj]

@RdoubleA I might be misunderstanding the code but I thought set_seed returned the seed you passed it in from the config (or if you don't pass anything, a global seed). I guess my intention here is to just pass in the seed from the config. Lmk if there is a better way to do it (maybe pass in cfg.seed directly?)

[RdoubleA]

Ah my bad, you're right. It's returning the global seed not the local seed. In that case this should be ok

[RdoubleA]

@EugenHotaj actually we might need to do something like this to get the seed directly from the config and maintaining BC with existing configs:
seed=cfg.get("seed", None) or 0

[EugenHotaj]

@RdoubleA done