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 2-[1-[(4-fluorophenyl)methyl]-2-methyl-4-oxo-6,7-dihydro-5H-indol-3-yl]-N-[(2R)-1-hydroxypropan-2-yl]acetamide is given. What is its corresponding molecular formula?
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C21H25FN2O3
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