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 9'-(4-pyren-1-ylphenyl)spiro[fluorene-9,12'-pentacyclo[11.8.0.02,11.03,8.015,20]henicosa-1(21),2(11),3,5,7,9,13,15,17,19-decaene] into molecular formula.
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C55H32
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