diff --git a/Lib/test/test_extcall.py b/Lib/test/test_extcall.py
index f1fff0a..a5af50b 100644
--- a/Lib/test/test_extcall.py
+++ b/Lib/test/test_extcall.py
@@ -1,3 +1,4 @@
+
 """Doctest for method/function calls.
 
 We're going the use these types for extra testing
@@ -65,17 +66,17 @@
     >>> g()
     Traceback (most recent call last):
       ...
-    TypeError: g() takes at least 1 positional argument (0 given)
+    TypeError: g() takes at least 1 argument (0 given)
 
     >>> g(*())
     Traceback (most recent call last):
       ...
-    TypeError: g() takes at least 1 positional argument (0 given)
+    TypeError: g() takes at least 1 argument (0 given)
 
     >>> g(*(), **{})
     Traceback (most recent call last):
       ...
-    TypeError: g() takes at least 1 positional argument (0 given)
+    TypeError: g() takes at least 1 argument (0 given)
 
     >>> g(1)
     1 () {}
@@ -261,13 +262,31 @@
     ...     print(a,b)
     >>> f(**x)
     1 2
+
+A obscure message:
+
+    >>> def f(a, b):
+    ...    pass
+    >>> f(b=1)
+    Traceback (most recent call last):
+      ...
+    TypeError: f() takes exactly 2 arguments (1 given)
+
+The number of arguments passed in includes keywords:
+
+    >>> def f(a):
+    ...    pass
+    >>> f(6, a=4, *(1, 2, 3))
+    Traceback (most recent call last):
+      ...
+    TypeError: f() takes exactly 1 argument (5 given)
 """
 
+import sys
 from test import support
 
 def test_main():
-    from test import test_extcall # self import
-    support.run_doctest(test_extcall, True)
+    support.run_doctest(sys.modules[__name__], True)
 
 if __name__ == '__main__':
     test_main()