You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-spiro[1-azabicyclo[2.2.2]octane-2,1'-cyclopropane]-3-yl-3,4-dihydro-2H-thieno[3,2-h]chromene-8-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C21H24N2O2S
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