You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-methyl-2-[(2S)-1-[3-(4-methylpyrazol-1-yl)propyl]pyrrolidin-2-yl]benzimidazole by IUPAC nomenclature, provide its molecular formula.
user
C19H25N5
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