You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-(2-fluorophenoxy)-N-methyl-N-[2-(4-methyl-2-oxo-3,4-dihydro-1H-1,5-benzodiazepin-5-yl)-2-oxoethyl]acetamide into its molecular formula.
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C21H22FN3O4
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