You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule [(5S,9S)-9-methoxy-1-oxa-7-azaspiro[4.4]nonan-7-yl]-(4-methyl-1,3-thiazol-5-yl)methanone into molecular formula.
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C13H18N2O3S
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