[Feature] Changes required for non public tenants (#370)

Co-authored-by: Tim Lorsbach <tim@lorsba.ch>
Reviewed-on: enviPath/enviPy#370

utilities/chem.py

@@ -88,6 +88,10 @@ class FormatConverter(object):
     def from_smiles(smiles):
         return Chem.MolFromSmiles(smiles)
 
+    @staticmethod
+    def from_molfile(molfile: str):
+        return Chem.MolFromMolBlock(molfile)
+
     @staticmethod
     def to_smiles(mol, canonical=False):
         return Chem.MolToSmiles(mol, canonical=canonical)
@@ -171,12 +175,17 @@ class FormatConverter(object):
             try:
                 Chem.Kekulize(mol)
             except Exception:
-                mc = Chem.Mol(mol.ToBinary())
+                mol = Chem.Mol(mol.ToBinary())
 
-        if not mc.GetNumConformers():
-            Chem.rdDepictor.Compute2DCoords(mc)
+        if not mol.GetNumConformers():
+            Chem.rdDepictor.Compute2DCoords(mol)
 
-        pass
+        drawer = rdMolDraw2D.MolDraw2DCairo(*mol_size)
+        opts = drawer.drawOptions()
+        opts.clearBackground = False
+        drawer.DrawMolecule(mol)
+        drawer.FinishDrawing()
+        return drawer.GetDrawingText()
 
     @staticmethod
     def normalize(smiles):