fixups

Author: rhshadrach

pandas/core/groupby/generic.py

@@ -888,9 +888,8 @@ def aggregate(self, func=None, *args, engine=None, engine_kwargs=None, **kwargs)
         relabeling, func, columns, order, _ = reconstruct_func(func, **kwargs)
         func = maybe_mangle_lambdas(func)
 
-        with group_selection_context(self):
-            op = GroupByApply(self, func, args, kwargs)
-            result = op.agg()
+        op = GroupByApply(self, func, args, kwargs)
+        result = op.agg()
         if not is_dict_like(func) and result is not None:
             return result
         elif relabeling and result is not None:
@@ -937,8 +936,6 @@ def aggregate(self, func=None, *args, engine=None, engine_kwargs=None, **kwargs)
                     gba = GroupByApply(self, [func], args=(), kwargs={})
                     try:
                         result = gba.agg()
-                        if get_option("new_udf_methods") and result is None:
-                            result = self._aggregate_frame(func)
 
                     except ValueError as err:
                         if "no results" not in str(err):
@@ -960,8 +957,7 @@ def aggregate(self, func=None, *args, engine=None, engine_kwargs=None, **kwargs)
                             )
                             # select everything except for the last level, which is the
                             # one containing the name of the function(s), see GH#32040
-                            if not get_option("new_udf_methods"):
-                                result.columns = result.columns.droplevel(-1)
+                            result.columns = result.columns.droplevel(-1)
 
         if not self.as_index:
             self._insert_inaxis_grouper_inplace(result)