You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-chloro-3'-(3-chloro-2-fluorophenyl)-2-methylspiro[indole-3,4'-pyrrolidine]-2'-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H16Cl2FN3O
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