You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2S)-6-[(4S)-3,3-difluoro-4-(1-methylcyclopropyl)pyrrolidin-1-yl]-7-fluoro-2-methyl-10-oxo-4-oxa-1-azatricyclo[7.3.1.05,13]trideca-5(13),6,8-triene-11-carboxylic acid by IUPAC nomenclature, provide its molecular formula.
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C21H23F3N2O4
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