You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 6-chloro-N-ethyl-N-[1-(3-methoxyphenyl)ethyl]-3,4-dihydro-2H-1,5-benzodioxepine-8-carboxamide into its molecular formula.
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C21H24ClNO4
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