You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [3-(3-chlorophenyl)-1,2,4-oxadiazol-5-yl]methyl (2S)-2-[(3aS,7aS)-1,3-dioxo-3a,4,5,6,7,7a-hexahydroisoindol-2-yl]propanoate by IUPAC nomenclature, provide its molecular formula.
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C20H20ClN3O5
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