You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-amino-1-cyclopropyl-7-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-6,8-difluoro-4-oxoquinoline-3-carboxylic acid into its molecular formula.
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C20H17F2N3O3S
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