You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-(3-chlorocarbazol-9-yl)-3-[4-(4-chlorophenyl)sulfonylpiperazin-1-yl]propan-2-ol by IUPAC nomenclature, provide its molecular formula.
user
C25H25Cl2N3O3S
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