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 2-[(3S,3aR)-3-(4-chlorophenyl)-7-methoxy-3,3a,4,5-tetrahydrobenzo[g]indazol-2-yl]-4-(4-chlorophenyl)-1,3-oxazole into molecular formula.
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C27H21Cl2N3O2
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