Patch# 1258 by Christian Heimes: kill basestring.
I like this because it makes the code shorter! :-)
diff --git a/Lib/email/feedparser.py b/Lib/email/feedparser.py
index 9ed8e4d..bff17ba 100644
--- a/Lib/email/feedparser.py
+++ b/Lib/email/feedparser.py
@@ -365,7 +365,7 @@
                                 self._last.epilogue = epilogue[:-end]
                     else:
                         payload = self._last.get_payload()
-                        if isinstance(payload, basestring):
+                        if isinstance(payload, str):
                             mo = NLCRE_eol.search(payload)
                             if mo:
                                 payload = payload[:-len(mo.group(0))]