Fix: Check if checkpoint_best_regular.pth exists before trying to copy it.

Author: Abdul-Mukit

rfdetr/main.py

@@ -473,7 +473,7 @@ def lr_lambda(current_step: int):
 
         best_is_ema = best_map_ema_5095 > best_map_5095
 
-        if utils.is_main_process():
+        if utils.is_main_process() and (output_dir / 'checkpoint_best_regular.pth').exists():
             if best_is_ema:
                 shutil.copy2(output_dir / 'checkpoint_best_ema.pth', output_dir / 'checkpoint_best_total.pth')
             else: