server-tools/auth_dynamic_groups/view/res_groups.xml

<openerp>
    <data>
        <record model="ir.ui.view" id="view_groups_form">
            <field name="inherit_id" ref="base.view_groups_form" />
            <field name="model">res.groups</field>
            <field name="arch" type="xml">
                <data>
                    <field name="name" position="after">
                        <field name="is_dynamic" />
                    </field>
                    <field name="users" position="attributes">
                        <attribute name="attrs">{'readonly': [('is_dynamic', '=', True)]}</attribute>
                    </field>
                    <field name="users" position="before">
                        <group name="auth_dynamic_groups" attrs="{'invisible': [('is_dynamic', '=', False)]}">
                            <field
                                name="dynamic_group_condition"
                                placeholder="Fill in your condition..."
                                attrs="{'required': [('is_dynamic', '=', True)]}"
                                colspan="4" nolabel="1" />
                            <button
                                type="object"
                                name="action_evaluate"
                                string="Evaluate" />
                        </group>
                    </field>
                </data>
            </field>
        </record>
    </data>
</openerp>