You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1,3-dibenzyl-3-[2-[2-[1-[(4-fluorophenyl)methyl]benzimidazole-2-carbonyl]piperidin-1-yl]ethyl]pyrrolidin-2-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C40H41FN4O2
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