REF: groupby internal names (pandas-dev#55551)

Author: gusthavoMFS

pandas/core/groupby/__init__.py

@@ -1,8 +1,8 @@
-from pandas.core.groupby.generic import (
-    DataFrameGroupBy,
-    NamedAgg,
-    SeriesGroupBy,
-)
+from pandas.core.groupby.generic import NamedAgg
+from pandas.core.groupby.frame_groupby import DataFrameGroupBy
+from pandas.core.groupby.series_groupby import SeriesGroupBy
+
+
 from pandas.core.groupby.groupby import GroupBy
 from pandas.core.groupby.grouper import Grouper
 
@@ -13,3 +13,4 @@
     "GroupBy",
     "Grouper",
 ]
+