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 (6R)-8-oxo-7-[(2-phenylacetyl)amino]-3-[(1-prop-2-ynyltetrazol-5-yl)sulfanylmethyl]-5-thia-1-azabicyclo[4.2.0]octane-3-carboxylic acid into molecular formula.
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C20H20N6O4S2
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