Question: How many heavy (non-hydrogen) atoms does this compound have?
 The Molecule has the SMILES Oc1cc(O)c2c(c1)O[C@H](c1ccc(O)c(O)c1)[C@@H](O)C2.
Answer: 21
{#Question|Q!}: {quest#}
{#Constraint:|Description:|!} The {#Molecule|Compound|Chemical!} {#has the|can be represented with the!} {SMILES__description} {SMILES#}.
{#Answer|Result|Answer!}: {answ#}
Oc1cc(O)c2c(c1)O[C@H](c1ccc(O)c(O)c1)[C@@H](O)C2
Oc1cc(O)c2c(c1)O[C@H](c1ccc(O)c(O)c1)[C@@H](O)C2
(2R,3S)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-chromene-3,5,7-triol
How many heavy (non-hydrogen) atoms does this compound have?