You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named acetylene;13,13-dimethyl-N-phenyl-N-(9,9'-spirobi[fluorene]-2-yl)-1-azapentacyclo[10.7.1.02,7.08,20.014,19]icosa-2(7),3,5,8(20),9,11,14,16,18-nonaen-4-amine by IUPAC nomenclature, provide its molecular formula.
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C54H38N2
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