You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-[2-(2-methoxyphenyl)pyrrolidin-1-yl]-2-oxoethyl]pyrrolo[1,2-d][1,2,4]triazin-1-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H20N4O3
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