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 7-pyridin-3-yl-2-(pyridin-3-ylmethyl)-1,3,3a,8b-tetrahydro-[1]benzothiolo[2,3-c]pyrrole 4,4-dioxide into its molecular formula.
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C21H19N3O2S
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