import tkinter as tk
from tkinter import ttk
class Gui:
    def __init__(self):
    	
        self.application_window = tk.Tk()
        self.add_modifier = tk.IntVar()
        self.create_widgets()
    def create_widgets(self):
        add_modifier = tk.Spinbox(self.application_window, from_=0, to=999)
        add_modifier.pack()
        button = ttk.Button(self.application_window, text='check', command=self.check)
        button.pack()
    def check(self):
        print(self.add_modifier.get())
program = Gui()
program.application_window.mainloop()

 import tkinter as tk
from tkinter import ttk
  
class Gui:
    def __init__(self):
        self.application_window = tk.Tk()
        self.create_widgets()
  
    def create_widgets(self):
        self.add_modifier = tk.Spinbox(self.application_window, from_=0, to=999)
        self.add_modifier.pack()
        button = ttk.Button(self.application_window, text='check', command=self.check)
        button.pack()
  
    def check(self):
        print(self.add_modifier.get())
 
 
program = Gui()
program.application_window.mainloop()

  
#!/usr/bin/env python3
 
import tkinter as tk
from tkinter.constants import *
 
class App(tk.Frame):
 
    def __init__(self, master=None):
        super().__init__(master)
        self.pack(fill=BOTH)
        self.create_widgets()
 
    def create_widgets(self):
        self.spin_box_var = tk.IntVar()
        self.spin_box = tk.Spinbox(
            self, from_=0, to=999, textvariable=self.spin_box_var)
        self.spin_box.pack()
        self.button_ok = tk.Button(self)
        self.button_ok.pack()
        self.button_ok.config(text='Ok', command=self.push_button_ok)
 
    def push_button_ok(self):
        print(self.spin_box_var.get())
 
 
if __name__ == '__main__':
    root = tk.Tk()
    win = App(root)
    win.master.title('Window')
    win.master.geometry('300x70+500+500')
    root.mainloop()

 dismiss_the_lowest = ttk.Checkbutton(self.application_window, variable=self.dismiss_the_lowest)