You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(1,9-dioxaspiro[5.5]undecan-4-yl)-2-[(4-methyl-1H-benzimidazol-2-yl)methoxy]acetamide into its molecular formula.
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C20H27N3O4
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