You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[[4-amino-5-[4-(difluoromethoxy)phenyl]-1,2,4-triazol-3-yl]sulfanyl]-1-(2-methyl-2,3-dihydroindol-1-yl)propan-1-one by IUPAC nomenclature, provide its molecular formula.
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C21H21F2N5O2S
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