You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3-[[4-(5-methyl-1,2-oxazole-3-carbonyl)-2-oxo-1-oxa-3,4-diazaspiro[4.5]decan-3-yl]methyl]benzonitrile into its molecular formula.
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C20H20N4O4
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