You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [(2S)-2-[5-[(2-chlorophenyl)methyl]-1,3-oxazol-2-yl]morpholin-4-yl]-pyridin-4-ylmethanone into its molecular formula.
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C20H18ClN3O3
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