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 methyl 7-[(2E,4Z)-hepta-2,4-dien-3-yl]-5-phenylpyrazolo[1,5-a]pyrimidine-2-carboxylate into molecular formula.
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C21H21N3O2
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