Commit

Author: StanFromIreland

Lib/traceback.py

@@ -1110,7 +1110,11 @@ def __init__(self, exc_type, exc_value, exc_traceback, *, limit=None,
         elif exc_type and issubclass(exc_type, ModuleNotFoundError):
             module_name = getattr(exc_value, "name", None)
             if module_name in sys.stdlib_module_names:
-                self._str = f"Standard library module '{module_name}' was not found"
+                message = _missing_stdlib_module.get(
+                    module_name,
+                    f"Standard library module '{module_name}' was not found"
+                )
+                self._str = message
             elif sys.flags.no_site:
                 self._str += (". Site initialization is disabled, did you forget to "
                     + "add the site-packages directory to sys.path "
@@ -1794,3 +1798,11 @@ def _levenshtein_distance(a, b, max_cost):
             # Everything in this row is too big, so bail early.
             return max_cost + 1
     return result
+
+_windows_only_modules = ["winreg", "msvcrt", "winsound", "nt", "_winapi", "_msi"]
+
+_missing_stdlib_module = {
+    name: f"Windows-only standard library module '{name}' not found"
+    for name in _windows_only_modules
+    # Distributors can patch this dictionary to provide installation suggestions.
+}