You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2,5-dichlorophenyl)-[4-(tetrazol-2-yl)phenyl]methanone;1-ethoxy-2,2-dimethylpropane by IUPAC nomenclature, provide its molecular formula.
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C21H24Cl2N4O2
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