diff --git a/social_core/backends/okta.py b/social_core/backends/okta.py
index 88abe984..2023c09f 100644
--- a/social_core/backends/okta.py
+++ b/social_core/backends/okta.py
@@ -28,19 +28,20 @@ def oidc_config_url(self):
         # If the URL path does not contain an authorizedServerId, we need
         # to truncate the path in order to generate a proper openid-configuration
         # URL.
-        if url.path == '/oauth2/':
-            url = url._replace(path='')
+        if url.path == "/oauth2/":
+            url = url._replace(path="")
 
         return urljoin(
             urlunparse(url),
-            './.well-known/openid-configuration?client_id={}'.format(
-                self.setting('KEY')
-            )
+            "./.well-known/openid-configuration?client_id={}".format(
+                self.setting("KEY")
+            ),
         )
 
     def oidc_config(self):
         return self.get_json(self.oidc_config_url())
 
+
 class OktaOAuth2(OktaMixin, BaseOAuth2):
     """Okta OAuth authentication backend"""
 
diff --git a/social_core/tests/backends/test_okta.py b/social_core/tests/backends/test_okta.py
index bf0184f1..967d2db6 100644
--- a/social_core/tests/backends/test_okta.py
+++ b/social_core/tests/backends/test_okta.py
@@ -145,23 +145,27 @@ def setUp(self):
         oidc_config = json.loads(self.openid_config_body)
 
         def jwks(_request, _uri, headers):
-            return 200, headers, json.dumps({'keys': [self.key]})
+            return 200, headers, json.dumps({"keys": [self.key]})
 
     def test_okta_oidc_config(self):
         # With no custom authorization server
-        self.strategy.set_settings({
-            'SOCIAL_AUTH_OKTA_OPENIDCONNECT_API_URL': 'https://dev-000000.oktapreview.com/oauth2',
-        })
+        self.strategy.set_settings(
+            {
+                "SOCIAL_AUTH_OKTA_OPENIDCONNECT_API_URL": "https://dev-000000.oktapreview.com/oauth2",
+            }
+        )
         self.assertEqual(
             self.backend.oidc_config_url(),
-            'https://dev-000000.oktapreview.com/.well-known/openid-configuration?client_id=a-key'
+            "https://dev-000000.oktapreview.com/.well-known/openid-configuration?client_id=a-key",
+        )
+        self.strategy.set_settings(
+            {
+                "SOCIAL_AUTH_OKTA_OPENIDCONNECT_API_URL": "https://dev-000000.oktapreview.com/oauth2/id-123456",
+            }
         )
-        self.strategy.set_settings({
-            'SOCIAL_AUTH_OKTA_OPENIDCONNECT_API_URL': 'https://dev-000000.oktapreview.com/oauth2/id-123456',
-        })
         self.assertEqual(
             self.backend.oidc_config_url(),
-            'https://dev-000000.oktapreview.com/oauth2/id-123456/.well-known/openid-configuration?client_id=a-key'
+            "https://dev-000000.oktapreview.com/oauth2/id-123456/.well-known/openid-configuration?client_id=a-key",
         )
 
         HTTPretty.register_uri(