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 (2Z)-2-cyano-N-(3-cyano-4,5,6,7-tetrahydro-1-benzothiophen-2-yl)-2-(1-ethyl-2-oxoindol-3-ylidene)acetamide into molecular formula.
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C22H18N4O2S
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