You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-ethyl-2-[(1-ethylimidazol-2-yl)methyl]-5,6,7,8-tetrahydro-4H-cyclohepta[c]pyrrol-4-amine is the IUPAC name of a molecule. Please give its molecular formula.
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C17H26N4
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