Whitespace normalization.
diff --git a/Lib/email/_compat21.py b/Lib/email/_compat21.py
index de8c447..d220723 100644
--- a/Lib/email/_compat21.py
+++ b/Lib/email/_compat21.py
@@ -31,7 +31,7 @@
 
 
 def _isstring(obj):
-    return isinstance(obj, StringType) or isinstance(obj, UnicodeType)    
+    return isinstance(obj, StringType) or isinstance(obj, UnicodeType)