You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2S)-1-[(6-chloro-7-methyl-2-oxochromen-4-yl)methyl]-2-methyl-2,3-dihydroindole-5-sulfonamide into molecular formula.
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C20H19ClN2O4S
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