You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-butyl-N-methyl-4-[(1R,2R,5S)-7-(pyridin-3-ylmethyl)-3,7-diazabicyclo[3.3.1]nonan-2-yl]butanamide into molecular formula.
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C22H36N4O
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