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-(3-cyano-4-ethyl-5-methylthiophen-2-yl)-8-ethoxy-2-iminochromene-3-carboxamide is given. What is its corresponding molecular formula?
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C20H19N3O3S
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