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propulate/propulator.py

@@ -489,6 +489,7 @@ def propulate(self, logging_interval: int = 10, debug: int = -1) -> None:
 
     def _intra_send_cleanup(self) -> None:
         """Delete all send buffers that have been sent."""
+        # Test for requests to complete.
         completed = MPI.Request.Testsome(self.intra_requests)
         # Remove requests and buffers of complete send operations.
         self.intra_requests = [r for i, r in enumerate(self.intra_requests) if i not in completed]