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What is the molecular formula of the molecule (6S)-7-[[2-amino-2-[3-(carboxymethylsulfanyl)phenyl]acetyl]amino]-8-oxo-3-[1-(2H-tetrazol-5-ylsulfanyl)ethyl]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid ?
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C20H21N7O6S3
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