Issue #26198: Fixed error messages for some argument parsing errors.
Fixed the documented about buffer overflow error for "es#" and "et#" format
units.
diff --git a/Lib/test/test_capi.py b/Lib/test/test_capi.py
index 6a8685c..96666d1 100644
--- a/Lib/test/test_capi.py
+++ b/Lib/test/test_capi.py
@@ -489,7 +489,7 @@
                     format.encode("ascii"), keywords)
                 when_not_skipped = False
             except TypeError as e:
-                s = "argument 1 must be impossible<bad format char>, not int"
+                s = "argument 1 (impossible<bad format char>)"
                 when_not_skipped = (str(e) == s)
             except RuntimeError as e:
                 when_not_skipped = False