You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[4-(3-oxo-7,8-dihydro-5H-pyrano[4,3-c]pyridazin-2-yl)cyclohexyl]azepane-1-sulfonamide into molecular formula.
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C19H30N4O4S
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