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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def confab_conformers(self, forcefield="mmff94", freeze_atoms=None, rmsd_cutoff=0.5, energy_cutoff=50.0, conf_cutoff=100000, verbose=False):
 """ Conformer generation based on Confab to generate all diverse low-energy conformers for molecules. This is different from rotor_conformer or gen3d_conformer as it aims to not simply to find a low energy conformation but to generate several different conformations. Args: forcefield (str):
 Default is mmff94. Options are 'gaff', 'ghemical', 'mmff94', 'mmff94s', and 'uff'. freeze_atoms ([int]):
 index of atoms to be freezed when performing conformer search, default is None. rmsd_cutoff (float):
 rmsd_cufoff, default is 0.5 Angstrom. energy_cutoff (float):
 energy_cutoff, default is 50.0 kcal/mol. conf_cutoff (float):
 max number of conformers to test, default is 1 million. verbose (bool):
 whether to display information on torsions found, default is False. Returns: (list):
 list of pymatgen Molecule objects for generated conformers. """

        if self._obmol.GetDimension() != 3:
            self.make3d()
        else:
            self.add_hydrogen()

        ff = ob.OBForceField_FindType(forcefield)
        if ff == 0:
            print("Could not find forcefield {} in openbabel, the forcefield "
                  "will be reset as default 'mmff94'".format(forcefield))
            ff = ob.OBForceField_FindType("mmff94")

        if freeze_atoms:
            print('{} atoms will be freezed'.format(len(freeze_atoms)))
            constraints = ob.OBFFConstraints()

            for atom in ob.OBMolAtomIter(self._obmol):
                atom_id = atom.GetIndex() + 1
                if id in freeze_atoms:
                    constraints.AddAtomConstraint(atom_id)
            ff.SetConstraints(constraints)

        # Confab conformer generation
        ff.DiverseConfGen(rmsd_cutoff, conf_cutoff, energy_cutoff,
                          verbose)
        ff.GetConformers(self._obmol)

        # Number of conformers generated by Confab conformer generation
        conformer_num = self._obmol.NumConformers()

        conformers = []
        for i in range(conformer_num):
            self._obmol.SetConformer(i)
            conformer = copy.deepcopy(BabelMolAdaptor(self._obmol).pymatgen_mol)
            conformers.append(conformer)
        self._obmol.SetConformer(0)
        return conformers