You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 7-(1H-imidazol-5-yl)-2-[(3R)-3-phenylpyrrolidin-1-yl]-3-propan-2-ylimidazo[2,1-f][1,2,4]triazin-4-one into molecular formula.
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C21H23N7O
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