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-[4-[(1R)-1-[[(2S)-1-propan-2-yloxypropan-2-yl]amino]ethyl]phenyl]pyridine-4-carboxamide into molecular formula.
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C20H27N3O2
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