old versions of models won't have produciton parameters, leading to ZeroDivision errors and breaking things

def check_production_parameters_exist(self):
        """ old versions of models won't have produciton parameters, leading to ZeroDivision errors and breaking things"""
        for k, v in self.modelInstance.parameter_sets.items():
            for p_id in self.modelInstance.production_params.keys():
                if v.get(p_id):
                    #print('{} already exists'.format(p_id))
                    pass
                else:
                    #print('No production parameter called {} - setting it to 1'.format(p_id))
                    v[p_id] = 1.0

            for p_id in self.modelInstance.allocation_params.keys():
                if v.get(p_id):
                    #print('{} already exists'.format(p_id))
                    pass
                else:
                    #print('No production parameter called {} - setting it to 1'.format(p_id))
                    v[p_id] = 1.0