chore: fix lint issues.

Author: liquor233

nemo/core/optim/optimizers.py

@@ -203,6 +203,15 @@ def get_optimizer(name: str, **kwargs: Optional[Dict[str, Any]]) -> Optimizer:
 
 
 def init_optimizer_states(optimizer: Optimizer):
+    """
+    Initialize optimizer states for Adam-based optimizers.
+
+    This function initializes the exponential moving averages (exp_avg and exp_avg_sq)
+    for Adam, AdamW, and FusedAdam optimizers if they haven't been initialized yet.
+
+    Args:
+        optimizer: The optimizer instance to initialize states for
+    """
     adam_nondist_optims = (optim.Adam, optim.AdamW)
     if HAVE_APEX:
         adam_nondist_optims += (FusedAdam,)