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Can you give the molecular formula of the molecule (6S,7R)-7-[[(2Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-methoxyiminoacetyl]amino]-3-[(7-methyl-1H-pyrazolo[1,5-a]pyridin-8-ium-3-yl)methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid ?
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C21H21N8O5S2+
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