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Co-authored-by: Petr Viktorin <[email protected]>

Author: chris-eibl

Lib/test/support/__init__.py

@@ -2588,8 +2588,9 @@ class Stopwatch:
     process_time does not exist everywhere (e.g. WASM).
 
     N.B.:
+    - This *includes* time spent in other threads/processes.
     - Some systems only have a coarse resolution; check
-      stopwatch.clock_info.resolution if.
+      stopwatch.clock_info.resolution when using the results.
 
     Usage: