Add support for deepspeed optimizer and custom scheduler (#1909)
* support for deepspeed optimizer and custom scheduler
* don't throw the error
* Add tests
* fix the tests
* fix the code quality
* Update tests/deepspeed/test_deepspeed.py
Co-authored-by: Benjamin Bossan <BenjaminBossan@users.noreply.github.com>
* fix the docstrings
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Co-authored-by: Benjamin Bossan <BenjaminBossan@users.noreply.github.com>