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 4-[5-[[(4aS,8aS)-4a-(hydroxymethyl)-1-methyl-3,4,5,6,8,8a-hexahydro-2H-1,7-naphthyridin-7-yl]methyl]thiophen-2-yl]-2-methylbut-3-yn-2-ol into molecular formula.
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C20H30N2O2S
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