* Added a new method flag, METH_COEXIST.

* Used the flag to optimize set.__contains__(), dict.__contains__(),
  dict.__getitem__(), and list.__getitem__().
diff --git a/Objects/methodobject.c b/Objects/methodobject.c
index 3a92fa4..5818616 100644
--- a/Objects/methodobject.c
+++ b/Objects/methodobject.c
@@ -67,7 +67,7 @@
 	PyObject *self = PyCFunction_GET_SELF(func);
 	int size;
 
-	switch (PyCFunction_GET_FLAGS(func) & ~(METH_CLASS | METH_STATIC)) {
+	switch (PyCFunction_GET_FLAGS(func) & ~(METH_CLASS | METH_STATIC | METH_COEXIST)) {
 	case METH_VARARGS:
 		if (kw == NULL || PyDict_Size(kw) == 0)
 			return (*meth)(self, arg);