You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [6-[(3-chloro-2-fluorophenyl)methyl]-7-(2-hydroxyethoxy)-1-(2-hydroxyethyl)-4-oxoquinolin-3-yl] hydrogen carbonate by IUPAC nomenclature, provide its molecular formula.
user
C21H19ClFNO7
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