You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(3,4-dichlorophenyl)-2-[(2S)-2-(1-methylpyrrol-2-yl)pyrrolidin-1-ium-1-yl]acetamide into its molecular formula.
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C17H20Cl2N3O+
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