You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[2-[(3,5-dimethyl-1-phenylpyrazol-4-yl)amino]-2-oxoethyl] 4-thiophen-2-ylbutanoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H23N3O3S
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