diff --git a/casanovo/config.py b/casanovo/config.py
index 4992a882..c07073d6 100644
--- a/casanovo/config.py
+++ b/casanovo/config.py
@@ -88,16 +88,12 @@ def __init__(self, config_file: Optional[str] = None):
                     keys_set = set(self._params.keys())
                     users_set = set(self._user_config.keys())
                     missing = list(keys_set - users_set)
-                    raise KeyError(
-                        f"Missing expected entry {missing}"
-                    )
+                    raise KeyError(f"Missing expected entry {missing}")
                 # detect unrecognized config file entries
                 keys = list(self._params.keys())
-                for key,val in self._user_config.items():
+                for key, val in self._user_config.items():
                     if key not in keys:
-                        raise KeyError(
-                            f"Unrecognized config file entry {key}"
-                        )
+                        raise KeyError(f"Unrecognized config file entry {key}")
         # Validate:
         for key, val in self._config_types.items():
             self.validate_param(key, val)
diff --git a/tests/conftest.py b/tests/conftest.py
index bbf51838..02d5015d 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -197,7 +197,7 @@ def tiny_config(tmp_path):
         "model_save_folder_path": str(tmp_path),
         "accelerator": "cpu",
         "precursor_mass_tol": 5,
-        "isotope_error_range": [0,1],
+        "isotope_error_range": [0, 1],
         "min_peptide_len": 6,
         "predict_batch_size": 1024,
         "n_beams": 1,
@@ -252,8 +252,8 @@ def tiny_config(tmp_path):
             "+42.011": 42.010565,      
             "+43.006": 43.005814,      
             "-17.027": -17.026549,     
-            "+43.006-17.027": 25.980265
-        }      
+            "+43.006-17.027": 25.980265,
+        },      
     }
 
     cfg_file = tmp_path / "config.yml"
diff --git a/tests/unit_tests/test_config.py b/tests/unit_tests/test_config.py
index ce695f93..4d1bb17f 100644
--- a/tests/unit_tests/test_config.py
+++ b/tests/unit_tests/test_config.py
@@ -28,16 +28,14 @@ def test_override(tmp_path, tiny_config):
 """
         )
 
-    with open (tiny_config, 'r') as read_file:
+    with open(tiny_config, "r") as read_file:
         contents = yaml.safe_load(read_file)
-        contents['random_seed_'] = 354
-        print(contents)
+        contents["random_seed_"] = 354
 
-    with open('output.yml', 'w') as write_file:
+    with open("output.yml", "w") as write_file:
         yaml.safe_dump(contents, write_file)
     with pytest.raises(KeyError):
-        config = Config('output.yml')
+        config = Config("output.yml")
     
     with pytest.raises(KeyError):
-        config = Config(yml)
-    
\ No newline at end of file
+        config = Config(yml)
\ No newline at end of file