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system
What is the molecular formula of the molecule identified by (7R,8S,9S,13S,14S,17R)-17-ethynyl-10,17-dihydroxy-7,13-dimethyl-2,6,7,8,9,11,12,14,15,16-decahydro-1H-cyclopenta[a]phenanthren-3-one ?
user
C21H28O3
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