GUI.py

import kivy
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.relativelayout import RelativeLayout
from kivy.core.window import Window
from kivy.uix.button import Button

from Scan import Scan

kivy.require('1.11.1')

class Odin(App):

    def __init__(self, parser, **kwargs):
        super().__init__(**kwargs)

        self.scan = Scan(parser)

    def build(self):
        return MainScreen(self.scan)

    def on_request_close(self, *args):
        self.scan.cleanup()
        return True

class MainScreen(RelativeLayout):

    def __init__(self, scan, **kwargs):
        Window.clearcolor = (1, 1, 1, 1)

        self.cols = 1
        self.scan = scan

        super(MainScreen, self).__init__(**kwargs)

        self.add_widget(Label(text="Odin", font_size='48', pos=(0, 200), color=[0, 0, 0, 1], font_name='Rajdhani-Bold.ttf'))

        self.scan_button = Button(text="Scan", size=(120, 50), size_hint=(None, None), pos=(348, 350))
        self.scan_button.bind(on_press=self.scan_onpress)
        self.add_widget(self.scan_button)

    def scan_onpress(self, instance):
        self.scan.scan()