You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule methyl 2-[6-(2-hydroxyethyl)-4,7-bis(2-methoxy-2-oxoethyl)-1,4,7,10-tetrazacyclododec-1-yl]acetate into molecular formula.
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C19H36N4O7
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