You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 1-[1-ethyl-3-(hydroxymethyl)-6,7-dihydro-4H-pyrazolo[4,3-c]pyridin-5-yl]-2-(5-phenyltetrazol-2-yl)ethanone .
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C18H21N7O2
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