minimalistic python service layer

I plan to have mysql/postgres database along with a thin service layer which I basically would like to us to receive restful requests and return results in json format. I'd like to use python for latter. Since I am new to python frameworks, if I'd use any for this thin layer which one would that be? The more minimalistic (thinner) the better of course.

Thanks for sharing your experience.

Juergen

PS: If it dealt with authentication/auhorization that would be a bonus.

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