You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (15R,19S)-15-methyl-17-oxapentacyclo[6.6.5.02,7.09,14.015,19]nonadeca-2,4,6,9,11,13-hexaene-16,18-dione into molecular formula.
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C19H14O3
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