fix: apply lintrunner

Author: e7217

torch/distributed/distributed_c10d.py

@@ -1342,11 +1342,13 @@ def get_backend(group: Optional[ProcessGroup] = None) -> Backend:
     pg = group or _get_default_group()
     if _rank_not_in_group(pg):
         raise ValueError("Invalid process group specified")
-    
+
     pg_store = _world.pg_map.get(pg, None)
     if pg_store is None:
-        raise ValueError(f"Process group {pg} is not initialized in the world group map. Please initialize the group first.")
-    
+        raise ValueError(
+            f"Process group {pg} is not initialized in the world group map. Please initialize the group first."
+        )
+
     return Backend(not_none(pg_store)[0])