You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (3Z)-3-hydroxyimino-4,7,7-trimethyl-N-(3-methylphenyl)-2-oxobicyclo[2.2.1]heptane-1-carboxamide into its molecular formula.
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C18H22N2O3
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