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,N-bis(2-chloroethyl)-3-methyl-2-oxo-4a,5,6,7,8,8a-hexahydro-4H-benzo[e][1,3,2]oxazaphosphinin-2-amine into molecular formula.
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C12H23Cl2N2O2P
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