How do you tag collaboration albums between solo artists? (eg. Freddie Gibbs & Madlib, Prodigy & Alchemist, Apollo Brown & OC, etc)

This one's been bugging me for a while, I've been putting the MC in the Artist field and the producer under Composer. But now I'm thinking I should put both MC & Producer under Artist...

Do you even care about tagging stuff?

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Gang Starr / Nujabes blend - https://youtu.be/lsci1vu6ick
DOOM Tribute - https://youtu.be/qmBQ2BDefKM
Donut of the Heart cover in Javascript - https://youtu.be/afLc2CkC8lk