diff --git a/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag b/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag
index a91354eef2..7a98c726e6 100755
--- a/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag
+++ b/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag
@@ -63,7 +63,7 @@ def run_sql_query(query: str) -> List[List[str]]:
             return []
         return [x.split("\0") for x in output.split("\n")]
     except subprocess.CalledProcessError as e:
-        report("CRITICAL", f"psql failed: {str(e)}: {e.output}")
+        report("CRITICAL", f"psql failed: {e}: {e.output}")
         sys.exit(MAXSTATE)
 
 
diff --git a/zerver/data_import/slack.py b/zerver/data_import/slack.py
index 1643c85bbf..6995581eb5 100644
--- a/zerver/data_import/slack.py
+++ b/zerver/data_import/slack.py
@@ -370,7 +370,7 @@ def build_customprofile_field(
             if field in slack_custom_fields:
                 field_name = field
             else:
-                field_name = f"Slack custom field {str(custom_profile_field_id + 1)}"
+                field_name = f"Slack custom field {custom_profile_field_id + 1}"
             customprofilefield = CustomProfileField(
                 id=custom_profile_field_id,
                 name=field_name,
diff --git a/zerver/lib/avatar_hash.py b/zerver/lib/avatar_hash.py
index 491b7ea074..9ace9d1096 100644
--- a/zerver/lib/avatar_hash.py
+++ b/zerver/lib/avatar_hash.py
@@ -35,7 +35,7 @@ def user_avatar_path(user_profile: UserProfile) -> str:
 
 def user_avatar_path_from_ids(user_profile_id: int, realm_id: int) -> str:
     user_id_hash = user_avatar_hash(str(user_profile_id))
-    return f"{str(realm_id)}/{user_id_hash}"
+    return f"{realm_id}/{user_id_hash}"
 
 
 def user_avatar_content_hash(ldap_avatar: bytes) -> str:
diff --git a/zerver/lib/test_classes.py b/zerver/lib/test_classes.py
index ac8db8d7a1..6470e6c82d 100644
--- a/zerver/lib/test_classes.py
+++ b/zerver/lib/test_classes.py
@@ -1171,7 +1171,7 @@ Output:
             for item in items:
                 print(item)
             print(f"\nexpected length: {count}\nactual length: {actual_count}")
-            raise AssertionError(f"{str(type(items))} is of unexpected size!")
+            raise AssertionError(f"{type(items)} is of unexpected size!")
 
     @contextmanager
     def assert_database_query_count(
diff --git a/zerver/openapi/openapi.py b/zerver/openapi/openapi.py
index cac83d1a9f..53a88b9269 100644
--- a/zerver/openapi/openapi.py
+++ b/zerver/openapi/openapi.py
@@ -558,5 +558,5 @@ See https://zulip.readthedocs.io/en/latest/documentation/api.html for help.
 
 The errors logged by the OpenAPI validator are below:\n"""
     for error in errors:
-        msg += f"* {str(error)}\n"
+        msg += f"* {error}\n"
     raise SchemaError(msg)
diff --git a/zerver/tests/test_push_notifications.py b/zerver/tests/test_push_notifications.py
index ccbf94bf05..4d1eae0591 100644
--- a/zerver/tests/test_push_notifications.py
+++ b/zerver/tests/test_push_notifications.py
@@ -1028,14 +1028,14 @@ class HandlePushNotificationTest(PushNotificationTest):
                 views_logger.output,
                 [
                     "INFO:zilencer.views:"
-                    f"Sending mobile push notifications for remote user 6cde5f7a-1f7e-4978-9716-49f69ebfc9fe:<id:{str(self.user_profile.id)}><uuid:{str(self.user_profile.uuid)}>: "
+                    f"Sending mobile push notifications for remote user 6cde5f7a-1f7e-4978-9716-49f69ebfc9fe:<id:{self.user_profile.id}><uuid:{self.user_profile.uuid}>: "
                     f"{len(gcm_devices)} via FCM devices, {len(apns_devices)} via APNs devices"
                 ],
             )
             for _, _, token in apns_devices:
                 self.assertIn(
                     "INFO:zerver.lib.push_notifications:"
-                    f"APNs: Success sending for user <id:{str(self.user_profile.id)}><uuid:{str(self.user_profile.uuid)}> to device {token}",
+                    f"APNs: Success sending for user <id:{self.user_profile.id}><uuid:{self.user_profile.uuid}> to device {token}",
                     pn_logger.output,
                 )
             for _, _, token in gcm_devices:
@@ -1089,7 +1089,7 @@ class HandlePushNotificationTest(PushNotificationTest):
                 views_logger.output,
                 [
                     "INFO:zilencer.views:"
-                    f"Sending mobile push notifications for remote user 6cde5f7a-1f7e-4978-9716-49f69ebfc9fe:<id:{str(self.user_profile.id)}><uuid:{str(self.user_profile.uuid)}>: "
+                    f"Sending mobile push notifications for remote user 6cde5f7a-1f7e-4978-9716-49f69ebfc9fe:<id:{self.user_profile.id}><uuid:{self.user_profile.uuid}>: "
                     f"{len(gcm_devices)} via FCM devices, {len(apns_devices)} via APNs devices"
                 ],
             )