1 files changed, 1 insertions, 1 deletions
diff --git a/Lib/smtpd.py b/Lib/smtpd.py
index 73e7777..2e09c5a 100755
--- a/Lib/smtpd.py
+++ b/Lib/smtpd.py
@@ -374,7 +374,7 @@ class PureProxy(SMTPServer):
 
 class MailmanProxy(PureProxy):
     def process_message(self, peer, mailfrom, rcpttos, data):
-        from cStringIO import StringIO
+        from io import StringIO
         from Mailman import Utils
         from Mailman import Message
         from Mailman import MailList