You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3H-benzimidazol-5-yl-[4-(2,5-dimethyl-1H-pyrrole-3-carbonyl)piperazin-1-yl]methanone into its molecular formula.
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C19H21N5O2
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