fix unused import

# This file is part of Tryton.  The COPYRIGHT file at the top level of

# this repository contains the full copyright notices and license terms.

from trytond.model import Workflow, ModelView, ModelSQL, fields, Unique

from trytond.pyson import Eval, If, Bool, Not, And, Or

from trytond.pyson import Eval, If, Not, Or

from trytond.transaction import Transaction

from trytond.pool import Pool

from trytond.i18n import gettext

    @ModelView.button

    @Workflow.transition('running')

    def run(cls, members):

        pool = Pool()

        for member in members:

            if not member.code:

                member.code = cls._new_code()