PEP 0492 -- Coroutines with async and await syntax. Issue #24017.
diff --git a/Parser/tokenizer.h b/Parser/tokenizer.h
index 1ce6eeb..3bcdad6 100644
--- a/Parser/tokenizer.h
+++ b/Parser/tokenizer.h
@@ -65,6 +65,13 @@
     const char* enc;        /* Encoding for the current str. */
     const char* str;
     const char* input; /* Tokenizer's newline translated copy of the string. */
+
+    int defstack[MAXINDENT];     /* stack if funcs & indents where they
+                                    were defined */
+    int deftypestack[MAXINDENT]; /* stack of func types
+                                    (0 not func; 1: "def name";
+                                     2: "async def name") */
+    int def;                     /* Length of stack of func types */
 };
 
 extern struct tok_state *PyTokenizer_FromString(const char *, int);