You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[2,5-dimethyl-1-(1,3-thiazol-2-yl)pyrrol-3-yl]-2-[1-(3-methoxyphenyl)imidazol-2-yl]sulfanylethanone by IUPAC nomenclature, provide its molecular formula.
user
C21H20N4O2S2
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