ultralytics 8.1.43 40% faster ultralytics imports (#9547)

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

ultralytics/engine/trainer.py

@@ -464,7 +464,7 @@ class BaseTrainer:
     def save_model(self):
         """Save model training checkpoints with additional metadata."""
         import io
-        import pandas as pd  # scope for faster startup
+        import pandas as pd  # scope for faster 'import ultralytics'
 
         # Serialize ckpt to a byte buffer once (faster than repeated torch.save() calls)
         buffer = io.BytesIO()