diff --git a/bitmask/bitmask.py b/bitmask/bitmask.py
index cedaa1c..018bae3 100644
--- a/bitmask/bitmask.py
+++ b/bitmask/bitmask.py
@@ -50,7 +50,7 @@ class Bitmask:
 
         self._value = 0
         # Placeholder, modified later in __mask_op()
-        self._AllFlags = IntFlag('', '')
+        self._AllFlags = IntFlag("", "")
 
         for flag in flags:
             self.add(flag)
@@ -90,7 +90,7 @@ class Bitmask:
             types.append(type_name(self.AllFlags))
 
         if len(types) > 1:
-            return ', '.join(types[:-1]) + " or " + types[-1]
+            return ", ".join(types[:-1]) + " or " + types[-1]
         else:
             return types[0]
 
@@ -113,13 +113,10 @@ class Bitmask:
                     return False
             else:
                 return True
-        elif issubclass(type(item), self.AllFlags) \
-                or not self.defined:
+        elif issubclass(type(item), self.AllFlags) or not self.defined:
             return bool(self.value & item)
         else:
-            raise TypeError(
-                f"item must be {self.__format_types()}"
-            )
+            raise TypeError(f"item must be {self.__format_types()}")
 
     def __iter__(self):
         """Return list of enabled flags."""
diff --git a/tests/test_bitmask.py b/tests/test_bitmask.py
index c0002d0..704872d 100644
--- a/tests/test_bitmask.py
+++ b/tests/test_bitmask.py
@@ -146,9 +146,9 @@ def test_and_operator():
     assert Bitmask() & Desc.ROUND == Bitmask()
 
     # AND of bitmasks
-    assert Bitmask(Desc.FUNKY, Desc.SONAR) & Bitmask(
-        Desc.FUNKY, Desc.ROUND
-    ) == Bitmask(Desc.FUNKY)
+    assert Bitmask(Desc.FUNKY, Desc.SONAR) & Bitmask(Desc.FUNKY, Desc.ROUND) == Bitmask(
+        Desc.FUNKY
+    )
     assert Bitmask(Desc.FUNKY, Desc.ROUND) & Bitmask(Desc.SMALL) == Bitmask()
     assert Bitmask() & Bitmask() == Bitmask()
 
@@ -207,8 +207,7 @@ def test_subtract():
         Desc.SMALL, Desc.ROUND
     ) == Bitmask(Desc.FUNKY)
     assert (
-        Bitmask(Desc.FUNKY, Desc.SMALL) - Bitmask(Desc.SMALL, Desc.FUNKY)
-        == Bitmask()
+        Bitmask(Desc.FUNKY, Desc.SMALL) - Bitmask(Desc.SMALL, Desc.FUNKY) == Bitmask()
     )
 
 
@@ -233,8 +232,7 @@ def test_xor_operator():
         Desc.SMALL, Desc.FUNKY, Desc.ROUND
     )
     assert (
-        Bitmask(Desc.FUNKY, Desc.ROUND) ^ Bitmask(Desc.FUNKY, Desc.ROUND)
-        == Bitmask()
+        Bitmask(Desc.FUNKY, Desc.ROUND) ^ Bitmask(Desc.FUNKY, Desc.ROUND) == Bitmask()
     )
     assert Bitmask() ^ Bitmask() == Bitmask()