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What is the molecular formula of the molecule identified by 2-[(8S,10S,13S,14S,17S)-10,13-dimethyl-3-oxo-1,2,6,7,8,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-17-yl]-2-oxoethanolate ?
user
C21H27O3-
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