Protein structure used does not change when using autodock_vina_descriptor.build()

[OliverT1]

When scoring multiple protein / ligand files using autodock_vina_descriptor the protein structure used is not changed, but the ligand file is changed. This means that all ligands are scored against the first protein used for autodock_vina_descriptor.build().

e.g.

proteins = ['protein1.pdb', 'protein2.pdb', 'protein3.pdb']
ligands = ['ligand1.sdf', 'ligand2.sdf', 'ligand3.sdf']
AV = autodock_vina_descriptor()
out = np.zeros((3, 6))
for i in range(len(proteins)):
    ligand_sdf = next(oddt.toolkit.readfile('sdf', ligands[i]))
    protein = next(oddt.toolkit.readfile('pdb', proteins[i]))
    protein.protein = True
    AVDs_all[i,:] = AV.build(protein = protein, ligands = ligand_sdf)

Expected behaviour: ligand1 scored against protein1, ligand2 scored against protein2, ligand3 scored against protein3
Actual behaviour: ligand1 scored against protein1, ligand2 scored against protein1, ligand3 scored against protein1
Temporary fix: Reinstantiate autodocok_vina_descriptor each time.

The analogous oddt_vina_descriptor behaves as expected.