ir_actions_report.xml

<?xml version="1.0" encoding="UTF-8" ?>
<odoo>
    <function model="ir.actions.report" name="unlink_action">
        <value eval="[ref('purchase.report_purchase_quotation')]" />
    </function>

    <record id="purchase.action_report_purchase_order" model="ir.actions.report">
        <field name="print_report_name">'Purchase Order - %s' % (object.name)</field>
    </record>

</odoo>