UPD: small steps to become python3 compatible.

dav_events/tests/test_emails.py

@@ -215,7 +215,7 @@ class EmailTestCase(EmailTestMixin, RoleMixin, TestCase):
         expected_body = EVENT_UPDATED_EMAIL_TEMPLATE.format(
             recipient_first_name=expected_recipient.first_name,
             editor_full_name=editor.get_full_name(),
-            event=unicode(self.event),
+            event=self.event,
             base_url=self.email_base_url,
             event_url=self.event.get_absolute_url(),
         )