You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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1-[1-[(3,4-dichlorophenyl)methyl]-3,5-dimethylpyrazol-4-yl]-3-[3-(3,5-dimethylpyrazol-1-yl)propyl]thiourea is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H26Cl2N6S
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