Patch# 1258 by Christian Heimes: kill basestring.
I like this because it makes the code shorter! :-)
diff --git a/Lib/zipfile.py b/Lib/zipfile.py
index c72c315..088f4a0 100644
--- a/Lib/zipfile.py
+++ b/Lib/zipfile.py
@@ -596,7 +596,7 @@
         self.pwd = None
 
         # Check if we were passed a file-like object
-        if isinstance(file, basestring):
+        if isinstance(file, str):
             # No, it's a filename
             self._filePassed = 0
             self.filename = file