You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named methyl 2-[(4Z)-4-[[3-ethoxy-4-(2-methoxy-2-oxoethoxy)phenyl]methylidene]-5-oxo-2-sulfanylideneimidazolidin-1-yl]acetate by IUPAC nomenclature, provide its molecular formula.
user
C18H20N2O7S
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