DOC: nice links / examples for setting with copy & aggregation
``SettingWithCopyWarning``
https://www.dataquest.io/blog/settingwithcopywarning/

``Aggregate/Filtering``
https://pythonforbiologists.com/when-to-use-aggregatefiltertransform-in-pandas/

I saw these nice blogs. At the very least we can add the links in our docs, maybe lift some text / examples.