Add some minor attributes and classes into stubs

[vharitonsky]

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1 out of 14 committers have signed the CLA.

:white_check_mark: KKawamura1
:x: Boryslav Larin
:x: brabadu
:x: AlexRiina
:x: wbolster
:x: item4
:x: DeanWay
:x: vharitonsky
:x: tiangolo
:x: tuffnatty
:x: tvuotila
:x: jdkandersson
:x: ilevkivskyi
:x: tdamsma

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