[Kivy] Acces atributes from a button defined in a class inside the .kv

[Tomli]

Hello!
Lately I have been trying my luck on kivy, and I'm always having problem when I try to access attributes that have been defined in the .kv

For example, this time I'm trying to access the attributes of my buttons inside my class SlidingPopup (id:btn_yes and id:btn_no) where I'm using it in the FloatLayout.

<SlidingPopup@GridLayout>:
    id:class_sliding
    btn_no: btn_no
    rows:2
    canvas:
        Color:
            rgba: 1,1,1,.8
        Rectangle:
            size: self.size
            pos: self.pos
    Label:
        text: "Are you sure?"
        font_size: 24
    GridLayout:
        rows: 1
        spacing: 10
        padding: 10
        Button:
            id: btn_no
            text: "No"
            color: 1,0,0,1
        Button:
            id: btn_yes
            text: "Yes"
            color: 0,0,0,1

FloatLayout:
    Button:
        size_hint: .3,.3
        pos_hint: {"center_x": .5, "center_y": .5}
        text:"Open Menu"
        on_release:
            app.show_the_button(the_sliding_menu)
    
    SlidingPopup:
        id: the_sliding_menu
        size_hint: 1, .3
        top_hint: 0
        pos_hint: {"top":self.top_hint, "right":1}

I'm just looking for a way to define their bindings where I'm using them and not in the class definition (something like btn_no.one_release: ... but that actually works :D). Someone who can give me a hand with their wisdom?