You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[5-fluoro-2-methyl-3-[4-(1,3-oxazol-5-yl)phenyl]sulfanylindol-1-yl]acetic acid into its molecular formula.
user
C20H15FN2O3S
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