You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-[4-[(4-chlorophenyl)methyl]piperazine-1,4-diium-1-yl]-1-(1,2,5-trimethylpyrrol-3-yl)ethanone into its molecular formula.
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C20H28ClN3O+2
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