You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (4S)-N-methyl-2-oxo-N-[(3-pyrazol-1-ylphenyl)methyl]-1-oxaspiro[4.4]nonane-4-carboxamide into its molecular formula.
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C20H23N3O3
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