TYP: pandas.core.series annotations from pandas-stubs
contains also changes in generic/frame.py but only to keep them consistent with series.py

edit: and added annotations for frame.py
Hello @twoertwein! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:

























There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2022-08-15 19:26:20 UTC Appears to be some typing failures > Appears to be some typing failures

The typing checks are now green :) Thanks @twoertwein (failures were unreleated)