如何在odoo8中创建日期向导

Question

我正在尝试创建一个向导来简化我的搜索。我已经创建了报表和xml，它工作得很好。然而，当我尝试搜索时，它会带来所有月份的工资单，而不是我选择的月份。因此，我尝试使用向导来过滤我的搜索。这是我的问题。在

我的向导代码是

import time
from datetime import datetime
from dateutil import relativedelta
from openerp.osv import fields, osv


class ReportWizard(osv.osv_memory):

    _name = 'bluspiral.sche.schedule'
#    _inherit = 'account.invoice'
    _description = 'Cash Payroll Schedule'

    _columns = {
        'date_from': fields.date('Date From', required=True),
        'date_to': fields.date('Date To', required=True),
    }

    _defaults = {
        'date_from': lambda *a: time.strftime('%Y-%m-01'),
        'date_to': lambda *a: str(datetime.now() + relativedelta.relativedelta(months=+1, day=1, days=-1))[:10],
    }

    def print_payroll_schedule_report(self, cr, uid, ids, context=None):
        datas = {}
        if context is None:
            context = {}
        data = self.read(cr, uid, ids,['date_from', 'date_to'],     context=context)
        date_from = data[0]['date_from']
        date_to = data[0]['date_to']
        obj = self.pool['hr.payslip']
        ids = obj.search(cr, uid, [('date_from','>=',date_from),    ('date_from','<=',date_to)])
        datas = {
                 'ids': ids,
                 'model': 'bluspiral.sche.schedule.template',
                 'form': data
                }
        return self.pool['report'].get_action(
            cr, uid, [], 'bluspiral_sche.cash_report', data=datas,     context=context
        )

我一直得到的错误是：

^{pr2}$

有什么想法吗？在