You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S)-2-(2,4-difluorophenyl)-N-[2-(1H-pyrazol-4-yl)ethyl]pyrrolidine-1-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H18F2N4O
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