You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 1-(2-piperidin-1-ylpyrimidin-5-yl)-N-(pyrazin-2-ylmethyl)piperidine-4-carboxamide is given. What is its corresponding molecular formula?
user
C20H27N7O
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