You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[(2S)-1-(3,4-dihydro-1H-isoquinolin-2-yl)-4-methyl-1-oxopentan-2-yl]oxolane-2-carboxamide into molecular formula.
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C20H28N2O3
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