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 (6-chloro-4-methyl-2,3-dihydroquinoxalin-1-yl)-(6-pyridin-2-yl-2,6-diazaspiro[3.3]heptan-2-yl)methanone into molecular formula.
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C20H22ClN5O
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