You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 6-benzyl-N-(3-hydroxypropyl)-5-methyl-7-oxo-1H-pyrazolo[1,5-a]pyrimidine-3-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C18H20N4O3
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