You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 13-ethyl-6,7,8-trimethoxy-16-(4-pyrazol-1-ylbutanoyl)-1,3,13,16,20-pentazatetracyclo[20.3.1.02,11.04,9]hexacosa-2,4,6,8,10-pentaen-19-one by IUPAC nomenclature, provide its molecular formula.
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C33H47N7O5
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