You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named [[4-[[3-[[4-[difluoro(phosphono)methyl]phenyl]methoxy]phenoxy]methyl]phenyl]-difluoromethyl]phosphonic acid is given. What is its corresponding molecular formula?
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C22H20F4O8P2
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