partner-contact/partner_identification/views/res_partner_id_category_view.xml

<?xml version="1.0" encoding="UTF-8" ?>
<odoo>
    <!-- Partner Identification Number Categories -->
    <record id="view_partner_id_category_form" model="ir.ui.view">
        <field name="name">res.partner.id_category.form</field>
        <field name="model">res.partner.id_category</field>
        <field name="type">form</field>
        <field name="arch" type="xml">
            <form string="Partner Identification Categories">
                <sheet>
                    <group>
                        <group>
                            <field name="name" />
                            <field name="code" />
                            <field name="validation_code" />
                        </group>
                        <group>
                            <div class="alert alert-primary" role="alert">
                                <h4>Python Validation Code:</h4>
                                <pre>
# Use failed = True to specify that the id number is not valid.
# You can use the following variables :
#  - self: browse_record of the current ID Category browse_record
#  - id_number: browse_record of ID number to validate

<b><i># Sample 1: ID number only contains digits</i></b>
if not id_number.name.isdigit():
    failed = True
else:
    failed = False

<b><i># Sample 2: Length of ID number cannot exceed 10 chars</i></b>
failed = len(id_number.name) > 10 and True or False

<b><i># Sample 3: ID number must start with the category code</i></b>
failed = not id_number.name.startswith(self.code) and True or False
                                </pre>
                            </div>
                        </group>
                    </group>
                </sheet>
            </form>
        </field>
    </record>
    <record id="view_partner_id_category_tree" model="ir.ui.view">
        <field name="name">res.partner.id_category.tree</field>
        <field name="model">res.partner.id_category</field>
        <field name="type">tree</field>
        <field name="arch" type="xml">
            <tree string="Partner Identification Categories">
                <field name="name" />
                <field name="code" />
            </tree>
        </field>
    </record>
    <record id="action_partner_id_category" model="ir.actions.act_window">
        <field name="name">Partner ID Categories</field>
        <field name="res_model">res.partner.id_category</field>
        <field name="view_mode">tree,form</field>
    </record>
    <menuitem
        action="action_partner_id_category"
        id="menu_partner_id_category"
        parent="contacts.res_partner_menu_config"
    />
</odoo>