You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4,5-dimethyl-12-phenyl-13-oxa-3,6-diazatricyclo[7.4.0.02,6]trideca-1(9),2,4,7-tetraene-8-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C19H19N3O2
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