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 4-(3-fluoro-4-methoxyphenyl)-2-(6-methylpyridin-2-yl)-5,6,7,8-tetrahydroquinazoline is given. What is its corresponding molecular formula?
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C21H20FN3O
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