You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 3-methyl-N-(8-methyl-2,4-dioxo-1,3-diazaspiro[4.5]decan-3-yl)-4-oxo-2-sulfanylidene-1H-quinazoline-7-carboxamide into molecular formula.
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C19H21N5O4S
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