You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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What is the molecular formula of the molecule identified by 1-(3a,4,5,6,7,7a-hexahydro-1,3-benzodioxol-5-ylmethyl)-4-[1-(imidazolidin-4-ylmethyl)piperidin-3-yl]piperazine ?
user
C21H39N5O2
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