1. Make the content to be published :
In[]:=
LabelMoleculeDrawing[image_]:=MoleculePlot[MoleculeRecognize[image],<|"Carbonyl"->Bond[{"C","O"},"Double"],"Ring carbons"->Atom["C","RingAtomQ"->True]|>]
In[]:=
LabelMoleculeDrawing
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2. Use the CloudDeploy function to publish to the cloud :
In[]:=
CloudDeploy[FormFunction[{"molecule"->"Image"},LabelMoleculeDrawing[#image]&,"JPEG",AppearanceRules->{"Title"->"Molecule recognizer"}],Permissions->"Public"]
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