fixed all of the pre-commit style errors for GH issue pandas-dev#58031

Author: longovin

pandas/core/groupby/ops.py

@@ -914,8 +914,7 @@ def agg_series(
         np.ndarray or ExtensionArray
         """
 
-
-        #if objtype is not in np.dtypes, type is preserved but thats bad seems readable 
+        # if objtype is not in np.dtypes, type is preserved
         if not isinstance(obj._values, np.ndarray) and obj.dtype != "boolean":
             # we can preserve a little bit more aggressively with EA dtype
             #  because maybe_cast_pointwise_result will do a try/except

pandas/tests/groupby/aggregate/test_other.py

@@ -667,19 +667,27 @@ def weird_func(x):
     result = df["decimals"].groupby(df["id1"]).agg(weird_func)
     tm.assert_series_equal(result, expected, check_names=False)
 
+
 def test_groupby_agg_boolean_dype():
     # GH Issue #58031
-    # Ensure return type of aggregate dtype has consistent behavior for 'bool' and 'boolean'
-    # because boolean not covered under numpy
-    
-    df_boolean = pd.DataFrame({0: [1, 2, 2], 1: [True, True, None]})
-    df_boolean[1] = df_boolean[1].astype("boolean")
-    
-    df_bool = pd.DataFrame({0: [1, 2, 2], 1: [True, True, None]})
-    df_bool[1] = df_bool[1].astype("bool")
-    
-    boolean_return_type = df_boolean.groupby(by=0).aggregate(lambda s: s.fillna(False).mean()).dtypes.values[0]
-    bool_return_type =   df_bool.groupby(by=0).aggregate(lambda s: s.fillna(False).mean()).dtypes.values[0]
-    
-    assert boolean_return_type == bool_return_type
+    # Ensure return type of aggregate dtype has consistent behavior
+    # for 'bool' and 'boolean' because boolean not covered under numpy
+
+    df_boolean = DataFrame({"0": [1, 2, 2], "1": [True, True, None]})
+    df_boolean[1] = df_boolean["1"].astype("boolean")
+
+    df_bool = DataFrame({"0": [1, 2, 2], "1": [True, True, None]})
+    df_bool[1] = df_bool["1"].astype("bool")
 
+    boolean_return_type = (
+        df_boolean.groupby("0")
+        .aggregate(lambda s: s.fillna(False).mean())
+        .dtypes.values[0]
+    )
+    bool_return_type = (
+        df_bool.groupby("0")
+        .aggregate(lambda s: s.fillna(False).mean())
+        .dtypes.values[0]
+    )
+
+    assert boolean_return_type == bool_return_type