Index: Python/pythonrun.c
===================================================================
--- Python/pythonrun.c	(revision 66009)
+++ Python/pythonrun.c	(working copy)
@@ -1301,9 +1301,10 @@
 	PyObject *type, *tb;
 
 	if (!PyExceptionInstance_Check(value)) {
-		PyFile_WriteString("TypeError: print_exception(): Exception expected for value, ", f);
-		PyFile_WriteString(Py_TYPE(value)->tp_name, f);
-		PyFile_WriteString(" found\n", f);
+		PyErr_Format(PyExc_TypeError,
+			     "Exception instance expected, not %.200s",
+			     Py_TYPE(f)->tp_name);
+		PyErr_WriteUnraisable(PyUnicode_FromString("print_exception"));
 		return;
 	}
 
Index: Lib/test/test_sys.py
===================================================================
--- Lib/test/test_sys.py	(revision 66009)
+++ Lib/test/test_sys.py	(working copy)
@@ -65,8 +65,7 @@
     def test_excepthook(self):
         with test.support.captured_output("stderr") as stderr:
             sys.excepthook(1, '1', 1)
-        self.assert_("TypeError: print_exception(): Exception expected for " \
-                         "value, str found" in stderr.getvalue())
+        self.assert_("Exception instance expected, not" in stderr.getvalue())
 
     # FIXME: testing the code for a lost or replaced excepthook in
     # Python/pythonrun.c::PyErr_PrintEx() is tricky.