You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[6-(2-oxo-2-pyrrolidin-1-ylethyl)sulfanylpyridazin-3-yl]-2-thiophen-2-ylacetamide into its molecular formula.
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C16H18N4O2S2
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