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What is the molecular formula of the molecule N-(9,9-dimethylfluoren-2-yl)-4'-[9,9-dimethyl-7-[(9-methyl-9-phenylfluoren-2-yl)-(9,9'-spirobi[fluorene]-3-yl)amino]fluoren-2-yl]-7-phenyl-N-(4-phenylphenyl)-9,9'-spirobi[fluorene]-3-amine ?
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C118H82N2
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