'return action to import bank/cash statements. This button should be called only on journals with type ==\'bank\''

@api.multi
def import_statement(self):

    action_name = 'action_account_bank_statement_import'
    [action] = self.env.ref(('account_bank_statement_import.%s' % action_name)).read()
    action.update({'context': ((u"{'journal_id':    " + str(self.id)) + u'}')})
    return action
