You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-(2-methylpropyl)pyrazol-3-yl]-4-oxo-4-(5-phenyl-3,4-dihydropyrazol-2-yl)butanamide The above is the IUPAC name of a molecule. Write its molecular formula.
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C20H25N5O2
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