You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 4,5-dimethyl-15-phenyl-13,14,16,17-tetrazatetracyclo[8.7.0.02,7.012,16]heptadeca-1(17),2(7),3,5,10,12,14-heptaene into molecular formula.
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C21H18N4
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