You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (1R,2S,6R,7S)-4-(2,6-diethyl-4-methylphenyl)-1-(hydroxymethyl)-10-oxatricyclo[5.2.1.02,6]decane-3,5-dione into molecular formula.
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C21H26O4
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