Example from crm_lead_view.xml:

        <record id="action_assign_salesman_according_assigned_partner" model="ir.actions.server">
            <field name="name">Assign salesman of assigned partner</field>
            <field name="model_id" ref="model_crm_lead"/>
            <field name="state">code</field>
            <field name="code">
                if context.get('active_model') == 'crm.lead':
                    ids = []
                    if context.get('active_domain'):
                        ids = self.search(cr, uid, context['active_domain'], context=context)
                    elif context.get('active_ids'):
                        ids = context['active_ids']
                    if ids:
                        self.assign_salesman_of_assigned_partner(cr, uid, ids, context=context)
            </field>
        </record>