diff --git dateutil/parser.py~ dateutil/parser.py
index 8b6c2d28b8..75453ef49e 100644
--- dateutil/parser.py~
+++ dateutil/parser.py
@@ -32,7 +32,7 @@ __all__ = ["parse", "parserinfo"]
 class _timelex(object):
 
     def __init__(self, instream):
-        if isinstance(instream, text_type):
+        if not hasattr(instream, 'read'):
             instream = StringIO(instream)
         self.instream = instream
         self.wordchars = ('abcdfeghijklmnopqrstuvwxyz'