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 2-[3-[3-(tert-butylamino)pyrrolidin-1-yl]-1,2,4-triazin-6-yl]-3-(hydroxymethyl)-5-(1H-pyrazol-4-yl)phenol into molecular formula.
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C21H27N7O2
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