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 6-methyl-2-N-(4-methylphenyl)-4-N-(5-phenyl-1H-pyrazol-3-yl)pyrimidine-2,4-diamine is given. What is its corresponding molecular formula?
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C21H20N6
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