You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-[(2S)-1-amino-3-(3,4-difluorophenyl)propan-2-yl]-4-(4-chloro-2-ethylpyrazol-3-yl)thiophene-2-carboxamide into molecular formula.
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C19H19ClF2N4OS
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