Extends `DataFrame.groupby` overloads to recognize some scalar index types#679

Merged

Dr-Irv merged 2 commits intopandas-dev:mainfrom

seantis:groupby-scalar-index

May 6, 2023

Commits on May 3, 2023

Extends groupby on dataframe to recognize some scalar index types
Daverball
committed

Commits on May 6, 2023

Make `GroupByDataFrame` generic. Add new `TypeVar` `ByT`.
Daverball
committed