You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[5-[4-[(5-chloro-2-methoxyphenyl)methyl]piperazine-1-carbonyl]-4-ethyl-2-methyl-1H-pyrrol-3-yl]ethanone into its molecular formula.
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C22H28ClN3O3
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