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 5-O-[2-(2-chloroethoxy)ethyl] 3-O-methyl 2,6-dimethyl-4-(3-nitrophenyl)-3,4-dihydropyridine-3,5-dicarboxylate is given. What is its corresponding molecular formula?
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C20H23ClN2O7
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