Issue #19526: Exclude all new API from the stable ABI.
diff --git a/Include/codecs.h b/Include/codecs.h
index 5ca505f..8f0014e 100644
--- a/Include/codecs.h
+++ b/Include/codecs.h
@@ -94,7 +94,7 @@
        const char *errors
        );
 
-#ifndef PY_LIMITED_API
+#ifndef Py_LIMITED_API
 /* Text codec specific encoding and decoding API.
 
    Checks the encoding against a list of codecs which do not