You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-(2,5-dioxo-6-phenyl-7H-imidazo[1,5-b][1,2,4]triazol-3-yl)-N-[(3-methoxyphenyl)methyl]acetamide into molecular formula.
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C20H19N5O4
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