diff -r 412c7daed0db Lib/tokenize.py
--- a/Lib/tokenize.py	Thu Jun 14 00:36:54 2012 +0200
+++ b/Lib/tokenize.py	Sat Jun 16 16:48:06 2012 +0300
@@ -70,10 +70,10 @@
 Single3 = r"[^'\\]*(?:(?:\\.|'(?!''))[^'\\]*)*'''"
 # Tail end of """ string.
 Double3 = r'[^"\\]*(?:(?:\\.|"(?!""))[^"\\]*)*"""'
-Triple = group("[uU]?[rR]?'''", '[uU]?[rR]?"""')
+Triple = group("[uUbB]?[rR]?'''", '[uUbB]?[rR]?"""')
 # Single-line ' or " string.
-String = group(r"[uU]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*'",
-               r'[uU]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*"')
+String = group(r"[uUbB]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*'",
+               r'[uUbB]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*"')
 
 # Because of leftmost-then-longest match semantics, be sure to put the
 # longest operators first (e.g., if = came before ==, == would get
@@ -91,9 +91,9 @@
 Token = Ignore + PlainToken
 
 # First (or only) line of ' or " string.
-ContStr = group(r"[uU]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*" +
+ContStr = group(r"[uUbB]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*" +
                 group("'", r'\\\r?\n'),
-                r'[uU]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*' +
+                r'[uUbB]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*' +
                 group('"', r'\\\r?\n'))
 PseudoExtras = group(r'\\\r?\n', Comment, Triple)
 PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name)