1 files changed, 8 insertions, 1 deletions
diff --git a/Lib/lib2to3/pgen2/tokenize.py b/Lib/lib2to3/pgen2/tokenize.py
index 701daf8..31e2969 100644
--- a/Lib/lib2to3/pgen2/tokenize.py
+++ b/Lib/lib2to3/pgen2/tokenize.py
@@ -38,6 +38,13 @@ __all__ = [x for x in dir(token) if x[0] != '_'] + ["tokenize",
            "generate_tokens", "untokenize"]
 del token
 
+try:
+    bytes
+except NameError:
+    # Support bytes type in Python <= 2.5, so 2to3 turns itself into
+    # valid Python 3 code.
+    bytes = str
+
 def group(*choices): return '(' + '|'.join(choices) + ')'
 def any(*choices): return group(*choices) + '*'
 def maybe(*choices): return group(*choices) + '?'
@@ -267,7 +274,7 @@ def detect_encoding(readline):
         try:
             return readline()
         except StopIteration:
-            return b''
+            return bytes()
 
     def find_cookie(line):
         try: