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 [6-hydroxy-1-(hydroxymethyl)-4,5-bis[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy]-2-oxabicyclo[2.2.0]hexan-3-yl] formate into molecular formula.
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C19H30O17
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