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 12-(2,6-dichloroanilino)-15-oxo-3,17-diaza-15-azoniatetracyclo[8.7.0.01,14.04,9]heptadeca-6,8,10-trien-5-ol is given. What is its corresponding molecular formula?
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C20H21Cl2N4O2+
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