fused_step may miss init_post_optimizer_step_hook

[todo]

bagua/bagua/torch_api/distributed.py

Lines 524 to 527 in 5add7f8

	# TODO: `fused_step` may miss `init_post_optimizer_step_hook`
	def new_step_factory(optimizer):
	def new_step(self, *args, **kwargs):
	result = self._bagua_original_step(*args, **kwargs)

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This issue was generated by todo based on a TODO comment in 5add7f8 when #207 was merged. cc @BaguaSys.