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 7-chloro-11-methyl-2-nitro-3-oxa-11-azatricyclo[6.4.1.04,13]trideca-1,4(13),5,7-tetraene into molecular formula.
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C12H11ClN2O3
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