You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (2,6-dichloropyridin-4-yl)-(7-methylidene-3,4,9,10-tetrahydro-2H-[1,4]dioxepino[2,3-g]isoquinolin-8-yl)methanone into molecular formula.
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C19H16Cl2N2O3
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