code: def delay_unscale():
      global DELAY_UNSCALE
  
      # delay_unscale is required for gradients accumulation, model accumulate
      # gradient on FP16 parameters when set to True and using the same loss_scale
      old_delay_unscale = DELAY_UNSCALE
      DELAY_UNSCALE = True
      try:
          yield
      finally:
          DELAY_UNSCALE = old_delay_unscale
  
imports: from contextlib import contextmanager
  from .None import cuda
label_desc: Use image node_id 1 for calling a global function with example usage: delay_unscale() without return types