Bytes literal.
diff --git a/Parser/Python.asdl b/Parser/Python.asdl
index ea11349..fd47aa0 100644
--- a/Parser/Python.asdl
+++ b/Parser/Python.asdl
@@ -60,6 +60,7 @@
 			 expr? starargs, expr? kwargs)
 	     | Num(object n) -- a number as a PyObject.
 	     | Str(string s) -- need to specify raw, unicode, etc?
+	     | Bytes(string s)
 	     | Ellipsis
 	     -- other literals? bools?
 
diff --git a/Parser/tokenizer.c b/Parser/tokenizer.c
index 84b7232..84bd60e 100644
--- a/Parser/tokenizer.c
+++ b/Parser/tokenizer.c
@@ -1244,6 +1244,14 @@
 			if (c == '"' || c == '\'')
 				goto letter_quote;
 			break;
+		case 'b':
+		case 'B':
+			c = tok_nextc(tok);
+			if (c == 'r' || c == 'R')
+				c = tok_nextc(tok);
+			if (c == '"' || c == '\'')
+				goto letter_quote;
+			break;
 		}
 		while (isalnum(c) || c == '_') {
 			c = tok_nextc(tok);