You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2E)-2-[(Z)-(3,4-dimethoxyphenyl)methylidenehydrazinylidene]-5-ethyl-3-[(4-fluorophenyl)methyl]-1,3-thiazolidin-4-one by IUPAC nomenclature, provide its molecular formula.
user
C21H22FN3O3S
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