You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2-[(5Z)-4,7-bis(carboxymethyl)-10-[(6-methoxypyridin-2-yl)methyl]-1,4,7,10-tetrazacyclododec-5-en-1-yl]acetic acid is given. What is its corresponding molecular formula?
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C21H31N5O7
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