You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[4-[2-(4-fluoroanilino)-2-oxoethyl]piperazin-1-yl]-N-[2-(4-fluorophenyl)ethyl]acetamide into its molecular formula.
user
C22H26F2N4O2
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