[ADD] display name of annex with prefix №

models/res_partner_contract_annex.py

@@ -10,6 +10,7 @@ class ContractOrderAnnex(models.Model):
     _description = "Contract Annex"
 
     name = fields.Char(string="Name",)
+    display_name = fields.Char(compute="_compute_display_name",)
     order_id = fields.Many2one(
         "sale.order",
         string="Order",
@@ -49,6 +50,12 @@ class ContractOrderAnnex(models.Model):
             }
         }
 
+    @api.multi
+    @api.depends('name')
+    def _compute_display_name(self):
+        for record in self:
+            record.display_name = "№{} {}".format(record.number or record.contract_id.contract_annex_number, record.name)
+
     @api.model
     def create(self, values):
         record = super().create(values)

views/res_partner_contract.xml

@@ -44,7 +44,7 @@
                     <group string="Annexed Specifications" name="annexes" attrs="{'invisible': [('id', '=', False)]}">
                         <field name="contract_annex_ids" nolabel="1">
                             <tree>
-                                <field name="name"/>
+                                <field name="display_name" string="Name"/>
                                 <button name="action_print_form" type="object" string="Print" attrs="{'invisible': [('id', '=', False)]}"/>
                             </tree>
                         </field>

views/res_partner_contract_annex.xml

@@ -12,6 +12,7 @@
                     <sheet>
                         <group>
                             <field name="name" placeholder="Leave empty for compute"/>
+                            <field name="display_name" invisible="1"/>
                             <field name="contract_id" attrs="{'invisible': [('contract_id', '=', False)]}"/>
                             <field name="order_id" options="{'no_create': True}"/>
                             <field name="date_conclusion"/>