diff --git a/Lib/test/test_format.py b/Lib/test/test_format.py
index 9924fde13e5..8afd5b8f1fa 100644
--- a/Lib/test/test_format.py
+++ b/Lib/test/test_format.py
@@ -274,7 +274,7 @@ def test_exc(formatstr, args, exception, excmsg):
         test_exc('%d', '1', TypeError, "%d format: a number is required, not str")
         test_exc('%x', '1', TypeError, "%x format: an integer is required, not str")
         test_exc('%x', 3.14, TypeError, "%x format: an integer is required, not float")
-        test_exc('%g', '1', TypeError, "a float is required")
+        test_exc('%g', '1', TypeError, "must be real number, not str")
         test_exc('no format', '1', TypeError,
                  "not all arguments converted during string formatting")
         test_exc('%c', -1, OverflowError, "%c arg not in range(0x110000)")