I'm trying to develop a small module to hide Graph view in purchase module and I tried the below way but not working with me. Any help on this will be appreciated.

What I did is below:

- created a group as below:

         <record id="view_price" model="res.groups">
            <field name="name">View All Prices</field>
            <field name="users" eval="[(4, ref('base.user_root'))]"/>
        </record>

   Then I tried to inherit the graph view and restrict access to the above group:

    

        <record model="ir.ui.view" id="hide_purchase_order_graph">
            <field name="model">purchase.order</field>
            <field name="inherit_id" ref="purchase.purchase_order_graph"/>
            <field name="arch" type="xml">
                <xpath expr="//field[@name='amount_total']" position="attributes">
                    <attribute name="groups">hide_prices.view_price</attribute>
                </xpath>
            </field>
        </record>