I have to create a view from the view "view_partner_tree"(base.res_partner) without touching the original. In the view that I create, I have to add some function field (not stored). I managed to create a new module displaying the view "view_partner_tree" on a different page. Would really kind of any of you to maybe guide me a bit through it or to give me a link that might help. (I have read anything google could find me with (inheritance, view)

_description = 'Aged Partner Balance'   
def _get_not_due(self, cr, uid, ids, name, arg, context):
    res = {}
    return res

_name = 'aged.partner.balance'
_columns = {
    'not_due': fields.function(_get_not_due, type='char', string="Not Due")       
    }   


    <record id="view_partner_tree" model="ir.ui.view">
        <field name="name">res.partner.tree</field>
        <field name="model">res.partner</field>
        <field eval="8" name="priority"/>
        <field name="arch" type="xml">
            <tree string="Contacts">
                <field name="name"/>
                <field name="function" invisible="1"/>
                <field name="phone"/>
                <field name="email"/>
                <field name="user_id" invisible="1" />
                <field name="is_company" invisible="1"/>
                <field name="country" invisible="1"/>
                <field name="country_id" invisible="1"/>
                <field name="parent_id" invisible="1"/>
            </tree>
        </field>
    </record>
   <record id="view_res_partner_filter" model="ir.ui.view">
        <field name="name">res.partner.select</field>
        <field name="model">res.partner</field>
        <field name="arch" type="xml">
            <search string="Search Partner">
               <field name="name"
                   filter_domain="['|','|',('name','ilike',self),('parent_id','ilike',self),('ref','=',self)]"/>
               <filter help="My Partners" icon="terp-personal+" domain="[('user_id','=',uid)]"/>
               <separator/>
               <filter string="Persons" name="type_person" icon="terp-personal" domain="[('is_company','=',0)]"/>
               <filter string="Companies" name="type_company" icon="terp-partner" domain="[('is_company','=',1)]"/>
               <separator/>
               <filter string="Customers" name="customer" icon="terp-personal" domain="[('customer','=',1)]" help="Customer Partners"/>
               <separator/>
               <filter string="Suppliers" name="supplier" icon="terp-personal" domain="[('supplier','=',1)]" help="Supplier Partners"/>
               <field name="category_id" string="Tag" filter_domain="[('category_id','ilike', self)]"/>
               <field name="user_id"/>
               <field name="parent_id" filter_domain="[('parent_id','child_of',[self])]"/>
               <group expand="0" string="Group By...">
                   <filter string="Salesperson" icon="terp-personal" domain="[]" context="{'group_by' : 'user_id'}" />
                   <filter string="Company" context="{'group_by': 'parent_id'}"/>
               </group>
           </search>
        </field>
    </record>


    <record id="action_partner_form" model="ir.actions.act_window">
        <field name="name">Aged Partner Balance</field>
        <field name="type">ir.actions.act_window</field>
        <field name="res_model">res.partner</field>
        <field name="view_type">form</field>
        <field name="view_mode">tree</field>
        <field name="context">{"search_default_customer":1}</field>
        <field name="search_view_id" ref="view_res_partner_filter"/>
    </record>

    <record id="action_partner_tree_view1" model="ir.actions.act_window.view">
        <field name="sequence" eval="1"/>
        <field name="view_mode">tree</field>
        <field name="view_id" ref="view_partner_tree2"/>
        <field name="act_window_id" ref="action_partner_form"/>
    </record>


    <menuitem id="menu_partner_form" parent="base.menu_sales" action="action_partner_form" sequence="1"/>
</data>

</openerp>