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 3-ethylpyridine-2-carbonitrile;6-[6-(3-ethylpyridin-2-yl)-1,4-dihydro-1,2,4,5-tetrazin-3-yl]pyridin-3-ol;hydrazine;5-hydroxypyridine-2-carbonitrile;hydrate is given. What is its corresponding molecular formula?
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C28H32N12O3
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