diff --git a/helpdesk/email.py b/helpdesk/email.py
index 33f15ca7..2af33f64 100644
--- a/helpdesk/email.py
+++ b/helpdesk/email.py
@@ -564,9 +564,7 @@ def create_ticket_cc(ticket, cc_list, logger):
                 "LOG_WARN_WHEN_CC_EMAIL_LINKED_TO_MORE_THAN_1_USER",
                 True,
             ):
-                logger.warning(
-                    f"{MULTIPLE_USERS_SAME_EMAIL_MSG}: {cced_email}"
-                )
+                logger.warning(f"{MULTIPLE_USERS_SAME_EMAIL_MSG}: {cced_email}")
         else:
             user_id = user_list[0]
 
diff --git a/helpdesk/tests/test_ticket_submission.py b/helpdesk/tests/test_ticket_submission.py
index 10951844..e2e5b3a2 100644
--- a/helpdesk/tests/test_ticket_submission.py
+++ b/helpdesk/tests/test_ticket_submission.py
@@ -18,7 +18,6 @@ from . import utils
 import logging
 from urllib.parse import urlparse
 import uuid
-import mock
 
 User = get_user_model()
 
@@ -488,33 +487,38 @@ class EmailInteractionsTestCase(TestCase):
         Verify that the duplicated email warning log is invoked
         """
         dup_email = "dup@helpdesk.test"
-        user_dup1 = User.objects.create(
-            username="User_dup1", email=dup_email,
+        User.objects.create(
+            username="User_dup1",
+            email=dup_email,
         )
-        user_dup2 = User.objects.create(
-            username="User_dup2", email=dup_email,
+        User.objects.create(
+            username="User_dup2",
+            email=dup_email,
         )
         message, _, _ = utils.generate_text_email(locale="fr_FR")
 
-        submitter_email = "foo@bar.py"
         cc_list = [dup_email, "alpha@acme.test", "beta@acme.test", "gamma@delta.test"]
         message_id = uuid.uuid4().hex
 
         message["Message-ID"] = message_id
         message["Cc"] = ",".join(cc_list)
 
-        with self.assertLogs('helpdesk', level='WARNING') as dup_warn:
+        with self.assertLogs("helpdesk", level="WARNING") as dup_warn:
             extract_email_metadata(str(message), self.queue_public, logger=logger)
-            self.assertTrue(MULTIPLE_USERS_SAME_EMAIL_MSG in dup_warn.output[0], "The duplicated email across user ID's was was not logged.")
+            self.assertTrue(
+                MULTIPLE_USERS_SAME_EMAIL_MSG in dup_warn.output[0],
+                "The duplicated email across user ID's was was not logged.",
+            )
         # Check that the CC duplicate was still sent a notification email
         email_count = len(mail.outbox)
         found = False
-        for i in range(0, email_count-1):
+        for i in range(0, email_count - 1):
             if dup_email in mail.outbox[i].to:
                 found = True
                 break
-        self.assertTrue(found, "The duplicated email across user ID's was not sent a n otification.")
-
+        self.assertTrue(
+            found, "The duplicated email across user ID's was not sent a n otification."
+        )
 
     def test_create_followup_from_email_with_valid_message_id_with_no_initial_cc_list(
         self,