Update orm.py

fields.function Writing is not standardized Since the conditions leading to the return value of the error caused by incomplete data
函数功能写法不规范，返回值由于条件导致数据不全引发报错

    def _get_employee(self, cr, uid, ids, field_name, args, context=None):
        res = {}
        for log in self.browse(cr,uid,ids,context=context):
            if log.employee_ids :
                res[log.id] = log.employee_ids[0].id
        return res
'employee_id': fields.function(_get_employee, string='Employee',
      type='many2one',relation="hr.employee"),