You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (9R,10S)-17-(cyclopropylmethyl)-10-hydroxy-17-azatetracyclo[7.5.3.01,10.02,7]heptadeca-2(7),3,5-triene-4-carboxamide into molecular formula.
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C21H28N2O2
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