I have a button in form view that inherited base.view_partner_form and when I clicked this button, I want to show tree view in another model.I try to create but External ID not found error is appeared.How can I fix it?Thank YouHere is my code.

in .xml file

<!--Create button-->

<record id="similar_list_view_partner_form" model="ir.ui.view">

        <field name="name">similar_list_view_partner_form</field>

        <field name="model">res.partner</field>

        <field name="inherit_id" ref="base.view_partner_form"></field>

        <field name="arch" type="xml">

                <xpath expr="//button[@name='toggle_active'][not(ancestor::field)]" position="after">

                          <button class="oe_stat_button" name="similar_list_button_action" type="object"                             icon="fa-align-justify"> <field name="show" readonly="1"/> </button>

               </xpath>

         </field>

</record>

<!--Create Tree View with three fields-->

<record id="similar_detail_tree_view" model="ir.ui.view">

    <field name="name">Similar Detail Tree View</field>

    <field name="model">similar.task</field>

     <field name="arch" type="xml">

        <tree>

                    <field name="similar_name"/>

                    <field name="similar_email"/>

                    <field name="similar_phone"/>

        </tree>

        </field>

</record>

In .py file

#function called by button to show tree view

class similar_contact(models.Model):

    _inherit= 'res.partner'

    show=fields.Char("Similar")

    @api.multi

    def similar_list_button_action(self):

        tree_view_id=self.env.ref('similar_task.similar_detail_tree_view').id       

        return {

                        'name':'Similar Detail Tree View',

                        'type':'ir.actions.act_window',

                        'res_model':'similar.task',

                        'view_mode':'tree',

                        'views':[(view_tree_id,'tree')],

                        'res_id':False,

                        'target':'new'

                }

#New model

class similar_detail(models.Model):

_name="similar.task"

similar_name=fields.Char("Name")

similar_email=fields.Char("Email")

similar_phone=fields.Char("Phone")