bpo-39573: Clean up modules and headers to use Py_IS_TYPE() function (GH-18521)

diff --git a/Modules/sha256module.c b/Modules/sha256module.c
index 0e0c446..eee582c 100644
--- a/Modules/sha256module.c
+++ b/Modules/sha256module.c
@@ -413,7 +413,7 @@
 {
     SHAobject *newobj;
 
-    if (Py_TYPE(self) == &SHA256type) {
+    if (Py_IS_TYPE(self, &SHA256type)) {
         if ( (newobj = newSHA256object())==NULL)
             return NULL;
     } else {