You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 3-(4-chlorophenyl)-5-(2-ethoxypyridin-3-yl)-2-(methoxymethyl)-1H-pyrazolo[1,5-a]pyrimidin-7-one is given. What is its corresponding molecular formula?
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C21H19ClN4O3
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