You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [3-amino-2-(2-bromophenyl)-4-cyano-6,6-dimethyl-5,8-dihydropyrano[3,4-c]pyridazin-1-yl] 2,2,2-trifluoroacetate by IUPAC nomenclature, provide its molecular formula.
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C18H16BrF3N4O3
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