You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (17-formyl-13-oxo-17-azatetracyclo[7.5.3.01,10.02,7]heptadeca-2(7),3,5-trien-3-yl) acetate into its molecular formula.
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C19H21NO4
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