diff --git a/cms/djangoapps/contentstore/signals/handlers.py b/cms/djangoapps/contentstore/signals/handlers.py
index b7fc7bc48b..478d99e94c 100644
--- a/cms/djangoapps/contentstore/signals/handlers.py
+++ b/cms/djangoapps/contentstore/signals/handlers.py
@@ -35,7 +35,7 @@ def locked(expiry_seconds, key):  # lint-amnesty, pylint: disable=missing-functi
     def task_decorator(func):
         @wraps(func)
         def wrapper(*args, **kwargs):
-            cache_key = '{}-{}'.format(func.__name__, kwargs[key])
+            cache_key = f'{func.__name__}-{kwargs[key]}'
             if cache.add(cache_key, "true", expiry_seconds):
                 log.info('Locking task in cache with key: %s for %s seconds', cache_key, expiry_seconds)
                 return func(*args, **kwargs)
diff --git a/cms/djangoapps/contentstore/tests/test_contentstore.py b/cms/djangoapps/contentstore/tests/test_contentstore.py
index 21a71b3f2f..343ff82740 100644
--- a/cms/djangoapps/contentstore/tests/test_contentstore.py
+++ b/cms/djangoapps/contentstore/tests/test_contentstore.py
@@ -1895,7 +1895,7 @@ class RerunCourseTest(ContentStoreTestCase):
 
     def get_unsucceeded_course_action_elements(self, html, course_key):
         """Returns the elements in the unsucceeded course action section that have the given course_key"""
-        return html.cssselect('.courses-processing li[data-course-key="{}"]'.format(str(course_key)))
+        return html.cssselect(f'.courses-processing li[data-course-key="{str(course_key)}"]')
 
     def assertInCourseListing(self, course_key):
         """
diff --git a/cms/djangoapps/contentstore/tests/test_course_settings.py b/cms/djangoapps/contentstore/tests/test_course_settings.py
index dc33590cd9..d0a81795ce 100644
--- a/cms/djangoapps/contentstore/tests/test_course_settings.py
+++ b/cms/djangoapps/contentstore/tests/test_course_settings.py
@@ -1645,7 +1645,7 @@ class CourseGraderUpdatesTest(CourseTestCase):
             "short_label": "yo momma",
             "weight": 17.3,
         }
-        resp = self.client.ajax_post('{}/{}'.format(self.url, len(self.starting_graders) + 1), grader)
+        resp = self.client.ajax_post(f'{self.url}/{len(self.starting_graders) + 1}', grader)
         self.assertEqual(resp.status_code, 200)
         obj = json.loads(resp.content.decode('utf-8'))
         self.assertEqual(obj['id'], len(self.starting_graders))
diff --git a/cms/djangoapps/contentstore/tests/test_libraries.py b/cms/djangoapps/contentstore/tests/test_libraries.py
index 0c5002b4b6..9ecb7da2cd 100644
--- a/cms/djangoapps/contentstore/tests/test_libraries.py
+++ b/cms/djangoapps/contentstore/tests/test_libraries.py
@@ -188,7 +188,7 @@ class TestLibraries(LibraryTestCase):
         # Create many blocks in the library and add them to a course:
         for num in range(8):
             ItemFactory.create(
-                data="This is #{}".format(num + 1),
+                data=f"This is #{num + 1}",
                 category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False
             )
 
diff --git a/cms/djangoapps/contentstore/tests/test_signals.py b/cms/djangoapps/contentstore/tests/test_signals.py
index c2ceda240e..e7eb6eadc0 100644
--- a/cms/djangoapps/contentstore/tests/test_signals.py
+++ b/cms/djangoapps/contentstore/tests/test_signals.py
@@ -35,7 +35,7 @@ class LockedTest(ModuleStoreTestCase):
 
         handle_grading_policy_changed(sender, course_key=str(self.course.id))
 
-        cache_key = 'handle_grading_policy_changed-{}'.format(str(self.course.id))
+        cache_key = f'handle_grading_policy_changed-{str(self.course.id)}'
         self.assertEqual(lock_available, compute_grades_async_mock.called)
         if lock_available:
             add_mock.assert_called_once_with(cache_key, "true", GRADING_POLICY_COUNTDOWN_SECONDS)
diff --git a/cms/djangoapps/contentstore/tests/test_utils.py b/cms/djangoapps/contentstore/tests/test_utils.py
index 6bf82b8bf0..78210894cc 100644
--- a/cms/djangoapps/contentstore/tests/test_utils.py
+++ b/cms/djangoapps/contentstore/tests/test_utils.py
@@ -1,13 +1,14 @@
 """ Tests for utils. """
 import collections
 from datetime import datetime, timedelta
+from unittest import mock
+from unittest.mock import Mock, patch
 from uuid import uuid4
 
 import ddt
 from django.conf import settings
 from django.test import TestCase
 from django.test.utils import override_settings
-from mock import Mock, mock, patch
 from opaque_keys.edx.locator import CourseLocator, LibraryLocator
 from path import Path as path
 from pytz import UTC
diff --git a/cms/djangoapps/contentstore/views/tabs.py b/cms/djangoapps/contentstore/views/tabs.py
index bfc8a4b3b7..251771ac60 100644
--- a/cms/djangoapps/contentstore/views/tabs.py
+++ b/cms/djangoapps/contentstore/views/tabs.py
@@ -111,7 +111,7 @@ def reorder_tabs_handler(course_item, request):
         CourseTabList.validate_tabs(new_tab_list)
     except InvalidTabsException as exception:
         return JsonResponse(
-            {"error": "New list of tabs is not valid: {}.".format(str(exception))}, status=400
+            {"error": f"New list of tabs is not valid: {str(exception)}."}, status=400
         )
 
     # persist the new order of the tabs
diff --git a/cms/djangoapps/contentstore/views/tests/test_certificates.py b/cms/djangoapps/contentstore/views/tests/test_certificates.py
index 10ad19f03c..6fc77d910f 100644
--- a/cms/djangoapps/contentstore/views/tests/test_certificates.py
+++ b/cms/djangoapps/contentstore/views/tests/test_certificates.py
@@ -715,7 +715,7 @@ class CertificatesDetailHandlerTestCase(
         image_asset_location = AssetKey.from_string(signatory['signature_image_path'])
         content = contentstore().find(image_asset_location)
         self.assertIsNotNone(content)
-        test_url = '{}/signatories/1'.format(self._url(cid=1))
+        test_url = f'{self._url(cid=1)}/signatories/1'
         response = self.client.delete(
             test_url,
             content_type="application/json",
@@ -737,7 +737,7 @@ class CertificatesDetailHandlerTestCase(
         Delete an signatory whose signature image is already removed or does not exist
         """
         self._add_course_certificates(count=2, signatory_count=4, asset_path_format=signatory_path)
-        test_url = '{}/signatories/3'.format(self._url(cid=1))
+        test_url = f'{self._url(cid=1)}/signatories/3'
         response = self.client.delete(
             test_url,
             content_type="application/json",
@@ -751,7 +751,7 @@ class CertificatesDetailHandlerTestCase(
         Try to delete a non existing certificate signatory. It should return status code 404 Not found.
         """
         self._add_course_certificates(count=2)
-        test_url = '{}/signatories/1'.format(self._url(cid=100))
+        test_url = f'{self._url(cid=100)}/signatories/1'
         response = self.client.delete(
             test_url,
             content_type="application/json",
diff --git a/cms/djangoapps/contentstore/views/tests/test_entrance_exam.py b/cms/djangoapps/contentstore/views/tests/test_entrance_exam.py
index 93f28b97ac..1fb7d8acfd 100644
--- a/cms/djangoapps/contentstore/views/tests/test_entrance_exam.py
+++ b/cms/djangoapps/contentstore/views/tests/test_entrance_exam.py
@@ -42,8 +42,8 @@ class EntranceExamHandlerTests(CourseTestCase, MilestonesTestCaseMixin):
         super().setUp()
         self.course_key = self.course.id
         self.usage_key = self.course.location
-        self.course_url = '/course/{}'.format(str(self.course.id))
-        self.exam_url = '/course/{}/entrance_exam/'.format(str(self.course.id))
+        self.course_url = f'/course/{str(self.course.id)}'
+        self.exam_url = f'/course/{str(self.course.id)}/entrance_exam/'
         self.milestone_relationship_types = milestones_helpers.get_milestone_relationship_types()
 
     def test_entrance_exam_milestone_addition(self):
diff --git a/cms/djangoapps/contentstore/views/tests/test_gating.py b/cms/djangoapps/contentstore/views/tests/test_gating.py
index 4b2ccb0508..d2f5da1525 100644
--- a/cms/djangoapps/contentstore/views/tests/test_gating.py
+++ b/cms/djangoapps/contentstore/views/tests/test_gating.py
@@ -134,8 +134,8 @@ class TestSubsectionGating(CourseTestCase):
         mock_is_prereq.return_value = True
         mock_get_required_content.return_value = str(self.seq1.location), min_score, min_completion
         mock_get_prereqs.return_value = [
-            {'namespace': '{}{}'.format(str(self.seq1.location), GATING_NAMESPACE_QUALIFIER)},
-            {'namespace': '{}{}'.format(str(self.seq2.location), GATING_NAMESPACE_QUALIFIER)}
+            {'namespace': f'{str(self.seq1.location)}{GATING_NAMESPACE_QUALIFIER}'},
+            {'namespace': f'{str(self.seq2.location)}{GATING_NAMESPACE_QUALIFIER}'}
         ]
         resp = json.loads(self.client.get_json(self.seq2_url).content.decode('utf-8'))
         mock_is_prereq.assert_called_with(self.course.id, self.seq2.location)
diff --git a/cms/djangoapps/contentstore/views/tests/test_helpers.py b/cms/djangoapps/contentstore/views/tests/test_helpers.py
index ad4c349ced..1c8db5a9f3 100644
--- a/cms/djangoapps/contentstore/views/tests/test_helpers.py
+++ b/cms/djangoapps/contentstore/views/tests/test_helpers.py
@@ -19,7 +19,7 @@ class HelpersTestCase(CourseTestCase):
     def test_xblock_studio_url(self):
 
         # Verify course URL
-        course_url = '/course/{}'.format(str(self.course.id))
+        course_url = f'/course/{str(self.course.id)}'
         self.assertEqual(xblock_studio_url(self.course), course_url)
 
         # Verify chapter URL
@@ -27,7 +27,7 @@ class HelpersTestCase(CourseTestCase):
                                      display_name="Week 1")
         self.assertEqual(
             xblock_studio_url(chapter),
-            '{}?show={}'.format(course_url, http.urlquote(str(chapter.location).encode()))
+            f'{course_url}?show={http.urlquote(str(chapter.location).encode())}'
         )
 
         # Verify sequential URL
@@ -35,7 +35,7 @@ class HelpersTestCase(CourseTestCase):
                                         display_name="Lesson 1")
         self.assertEqual(
             xblock_studio_url(sequential),
-            '{}?show={}'.format(course_url, http.urlquote(str(sequential.location).encode()))
+            f'{course_url}?show={http.urlquote(str(sequential.location).encode())}'
         )
 
         # Verify unit URL
@@ -55,7 +55,7 @@ class HelpersTestCase(CourseTestCase):
 
         # Verify library URL
         library = LibraryFactory.create()
-        expected_url = '/library/{}'.format(str(library.location.library_key))
+        expected_url = f'/library/{str(library.location.library_key)}'
         self.assertEqual(xblock_studio_url(library), expected_url)
 
     def test_xblock_type_display_name(self):
diff --git a/cms/djangoapps/contentstore/views/tests/test_import_export.py b/cms/djangoapps/contentstore/views/tests/test_import_export.py
index f14a2f5f29..aec9190c82 100644
--- a/cms/djangoapps/contentstore/views/tests/test_import_export.py
+++ b/cms/djangoapps/contentstore/views/tests/test_import_export.py
@@ -113,7 +113,7 @@ class ImportEntranceExamTestCase(CourseTestCase, MilestonesTestCaseMixin):
         """
         Check that pre existed entrance exam content should be overwrite with the imported course.
         """
-        exam_url = '/course/{}/entrance_exam/'.format(str(self.course.id))
+        exam_url = f'/course/{str(self.course.id)}/entrance_exam/'
         resp = self.client.post(exam_url, {'entrance_exam_minimum_score_pct': 0.5}, http_accept='application/json')
         self.assertEqual(resp.status_code, 201)