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 propan-2-yl 4-amino-6-chloro-5-fluoropyridine-2-carboxylate;propan-2-yl 4-amino-5,6-difluoropyridine-2-carboxylate is given. What is its corresponding molecular formula?
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C18H20ClF3N4O4
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