You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 7-[2-(2-ethylpiperidin-1-yl)-2-oxoethyl]-7-azabicyclo[2.2.1]heptane-2-carboxylic acid by IUPAC nomenclature, provide its molecular formula.
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C16H26N2O3
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