You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N,N-dimethyl-3-[1-(thiophene-2-carbonyl)piperidin-3-yl]thieno[2,3-b]pyridine-2-carboxamide is given. What is its corresponding molecular formula?
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C20H21N3O2S2
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