fix wrong docstring (#262)

Author: samsja

torchft/local_sgd.py

@@ -561,8 +561,8 @@ def _allreduce_bucketized(self) -> None:
 
 class DiLoCo:
     """
-    DiLoCo is a subclass of LocalSGD that overrides the synchronization
-    mechanism to average and synchronize the pseudogradients (delta of the previous global weight and current local weights).
+    DiLoCo implements distributed optimization by averaging and synchronizing
+    pseudogradients (delta of the previous global weight and current local weights).
 
     The class implements a more general version of DiLoco, Streaming DiLoCo,
     which synchronizes fragments of pseudogradients at different steps.