<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_interaction_energy(self, assign_ff=True, ff=None, mol2=False, force_ff_assign=False):
 """Calculates the interaction energy of the AMPAL object. Parameters assign_ff: bool, optional If true the force field will be updated if required. ff: BuffForceField, optional The force field to be used for scoring. mol2: bool, optional If true, mol2 style labels will also be used. force_ff_assign: bool, optional If true, the force field will be completely reassigned, ignoring the cached parameters. Returns ------- buff_score: buff.BUFFScore A BUFFScore object with information about each of the interactions and the `Atoms` involved. Raises ------ AttributeError Raise if a component molecule does not have an `update_ff` method. """

        if not ff:
            ff = global_settings['buff']['force_field']
        if assign_ff:
            for molecule in self._molecules:
                if hasattr(molecule, 'update_ff'):
                    molecule.update_ff(
                        ff, mol2=mol2, force_ff_assign=force_ff_assign)
                else:
                    raise AttributeError(
                        'The following molecule does not have a update_ff'
                        'method:\n{}\nIf this is a custom molecule type it'
                        'should inherit from BaseAmpal:'.format(molecule))
        interactions = find_inter_ampal(self, ff.distance_cutoff)
        buff_score = score_interactions(interactions, ff)
        return buff_score