I try to install 'hr_payroll_cancel'  module in odoo 8 (it is version 7 module ),that time I got this error   lxml.etree._Validator.assert_ (src/lxml/lxml.etree.c:159862) AssertionError: Invalid attribute model for element field,

Error is came from  this  'hr_payslip_workflow.xml' xml ,if I comment this xml from openerp.py then it is installed otherwise it shows below error

 lxml.etree._Validator.assert_ (src/lxml/lxml.etree.c:159862) AssertionError: Invalid attribute model for  element field

How can I change this workflow.xml for installing module in version 8---------

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <record id="hr_payroll.act_done" model="workflow.activity">
            <field name="wkf_id" ref="hr_payroll.wkf"/>
            <field name="name">done</field>
            <field name="action">process_sheet()</field>
            <field name="kind">function</field>
            <field name="flow_stop"></field>
        </record>
        
        <record id="workflow_transition_act_done_to_act_cancel" model="workflow.transition">
            <field name="signal">cancel_sheet</field>
            <field model="workflow.activity" name="act_from" ref="hr_payroll.act_done"/>
            <field model="workflow.activity" name="act_to" ref="hr_payroll.act_cancel"/>
            <field name="condition">True</field>
        </record>
        
    </data>
</openerp>