bpo-38787: Add PyCFunction_CheckExact() macro for exact type checks (GH-20024)



… now that we allow subtypes of PyCFunction.

Also add PyCMethod_CheckExact() and PyCMethod_Check() for checks against the PyCMethod subtype.
diff --git a/Include/cpython/methodobject.h b/Include/cpython/methodobject.h
index 2ac2cbf..7ecbfe3 100644
--- a/Include/cpython/methodobject.h
+++ b/Include/cpython/methodobject.h
@@ -4,6 +4,9 @@
 
 PyAPI_DATA(PyTypeObject) PyCMethod_Type;
 
+#define PyCMethod_CheckExact(op) Py_IS_TYPE(op, &PyCMethod_Type)
+#define PyCMethod_Check(op) PyObject_TypeCheck(op, &PyCMethod_Type)
+
 /* Macros for direct access to these values. Type checks are *not*
    done, so use with care. */
 #define PyCFunction_GET_FUNCTION(func) \