You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named [(3R)-4-[(4-fluorophenyl)methyl]-3-propan-2-yl-1,4-diazepan-1-yl]-(5-fluoropyridin-3-yl)methanone is given. What is its corresponding molecular formula?
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C21H25F2N3O
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