You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name tert-butyl N-methyl-N-[2-[[1-(1-methyl-2-oxo-3H-indol-5-yl)pyrazol-3-yl]methoxy]ethyl]carbamate into its molecular formula.
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C21H28N4O4
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