You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[(1,1-dioxothiolan-3-yl)methyl]-3-[5-ethyl-1-(2-methylpropyl)pyrazol-4-yl]urea by IUPAC nomenclature, provide its molecular formula.
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C15H26N4O3S
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