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 2-N-butan-2-yl-2-N-ethyl-7-methoxy-1-N-methyl-1,2,3,4-tetrahydronaphthalene-1,2-diamine into molecular formula.
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C18H30N2O
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