manufacture/mrp_multi_level/wizards/mrp_multi_level_view.xml

<?xml version="1.0"?>
<odoo>

    <record id="view_run_mrp_multi_level_wizard" model="ir.ui.view">
        <field name="name">Run MRP</field>
        <field name="model">mrp.multi.level</field>
        <field name="arch" type="xml">
            <form string="Run MRP Multi Level">
                <footer>
                    <button name="run_mrp_multi_level" string="Run MRP" type="object"  class="oe_highlight"  />
                    or
                    <button string="Cancel" class="oe_link" special="cancel" />
                </footer>
            </form>
        </field>
    </record>

    <act_window name="Run MRP"
            res_model="mrp.multi.level"
            src_model="mrp.multi.level"
            view_mode="form"
            target="new"
            key2="client_action_multi"
            id="action_mrp_multi_level"/>

</odoo>