diff --git a/sqlite_utils/db.py b/sqlite_utils/db.py
index 5972032..7cc1c99 100644
--- a/sqlite_utils/db.py
+++ b/sqlite_utils/db.py
@@ -414,7 +414,9 @@ class Database:
             fn_name = name or fn.__name__
             arity = len(inspect.signature(fn).parameters)
             if not replace and (fn_name, arity) in self._registered_functions:
-                raise FunctionAlreadyRegistered(f'Already registered function with name "{fn_name}" and identical arity')
+                raise FunctionAlreadyRegistered(
+                    f'Already registered function with name "{fn_name}" and identical arity'
+                )
             kwargs = {}
             registered = False
             if deterministic:
@@ -2693,15 +2695,17 @@ class Table(Queryable):
                 return jsonify_if_needed(fn(v))
 
             fn_name = fn.__name__
-            if fn_name == '<lambda>':
-                fn_name = f'lambda_{hash(fn)}'
+            if fn_name == "<lambda>":
+                fn_name = f"lambda_{hash(fn)}"
             self.db.register_function(convert_value, name=fn_name)
             sql = "update [{table}] set {sets}{where};".format(
                 table=self.name,
                 sets=", ".join(
                     [
                         "[{output_column}] = {fn_name}([{column}])".format(
-                            output_column=output or column, column=column, fn_name=fn_name
+                            output_column=output or column,
+                            column=column,
+                            fn_name=fn_name,
                         )
                         for column in columns
                     ]
diff --git a/tests/test_convert.py b/tests/test_convert.py
index 8fffb4a..5279bc5 100644
--- a/tests/test_convert.py
+++ b/tests/test_convert.py
@@ -153,6 +153,6 @@ def test_convert_repeated(fresh_db):
     table = fresh_db["table"]
     col = "num"
     table.insert({col: 1})
-    table.convert(col, lambda x: x*2)
+    table.convert(col, lambda x: x * 2)
     table.convert(col, lambda _x: 0)
     assert table.get(1) == {col: 0}
diff --git a/tests/test_register_function.py b/tests/test_register_function.py
index 05721ea..5b92631 100644
--- a/tests/test_register_function.py
+++ b/tests/test_register_function.py
@@ -5,6 +5,7 @@ from unittest.mock import MagicMock, call
 from sqlite_utils.utils import sqlite3
 from sqlite_utils.db import FunctionAlreadyRegistered
 
+
 def test_register_function(fresh_db):
     @fresh_db.register_function
     def reverse_string(s):
@@ -86,6 +87,7 @@ def test_register_function_replace(fresh_db):
 
     # This will fail to replace the function:
     with pytest.raises(FunctionAlreadyRegistered):
+
         @fresh_db.register_function()
         def one():  # noqa
             return "two"
@@ -103,6 +105,7 @@ def test_register_function_replace(fresh_db):
 def test_register_function_duplicate(fresh_db):
     def to_lower(s):
         return s.lower()
+
     fresh_db.register_function(to_lower)
     with pytest.raises(FunctionAlreadyRegistered):
         fresh_db.register_function(to_lower)