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 1-[3-(hydroxymethyl)-1-methyl-6,7-dihydro-4H-pyrazolo[4,3-c]pyridin-5-yl]-2-[(6-methyl-1H-benzimidazol-2-yl)sulfanyl]ethanone into molecular formula.
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C18H21N5O2S
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