You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[8-[(5-cyanopyridin-2-yl)carbamoyl]-2-(dimethoxymethyl)-6,7-dihydro-5H-1,8-naphthyridin-3-yl]acetic acid into molecular formula.
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C20H21N5O5
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