diff --git a/atmosphere/config/__init__.py b/atmosphere/config/__init__.py
index 98bf87e..5d8dcb8 100644
--- a/atmosphere/config/__init__.py
+++ b/atmosphere/config/__init__.py
@@ -10,7 +10,7 @@
 _root_config.register_child_config(images.config_group)
 _root_config.register_child_config(memcached.config_group)
 
-CONFIG_FILE = os.environ.get('ATMOSPHERE_CONFIG', '/etc/atmosphere/config.toml')
+CONFIG_FILE = os.environ.get("ATMOSPHERE_CONFIG", "/etc/atmosphere/config.toml")
 
 
 def _load_config():
diff --git a/atmosphere/tests/unit/models/openstack_helm/test_images.py b/atmosphere/tests/unit/models/openstack_helm/test_images.py
index 556c6aa..c529c49 100644
--- a/atmosphere/tests/unit/models/openstack_helm/test_images.py
+++ b/atmosphere/tests/unit/models/openstack_helm/test_images.py
@@ -18,7 +18,9 @@
     CONF,
     {
         "atmosphere.images.memcached": [{"operation": "override", "value": "foo"}],
-        "atmosphere.images.memcached_exporter": [{"operation": "override", "value": "bar"}],
+        "atmosphere.images.memcached_exporter": [
+            {"operation": "override", "value": "bar"}
+        ],
     },
 )
 def test_images_for_chart_memcached_with_overrides():