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 N-[(4-fluorophenyl)methyl]-2-[[5-(1H-indol-3-ylmethyl)-1,3,4-oxadiazol-2-yl]sulfanyl]acetamide into molecular formula.
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C20H17FN4O2S
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