You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 4-[2-[2-(2,6-difluoro-4-propylphenyl)ethynyl]thieno[3,2-b]thiophen-5-yl]-3-ethyl-2,6-difluorobenzaldehyde into molecular formula.
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C26H18F4OS2
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