This is a simple graphic user interface for converting kilogram to grams, pounds and ounces.

from tkinter import *


def convert_kg():
    gram_label.set(str(int(user_input_entry.get()) * 1000)+"g")
    pound_label.set(str(float(user_input_entry.get()) * 2.20462)+"pounds")
    ounce_label.set(str(float(user_input_entry.get()) * 35.274)+"ounces")


win = Tk()

kg_label = Label(win, text="KG")
kg_label.grid(row=0, column=0)

user_input_entry = StringVar()
user_input = Entry(win, textvariable=user_input_entry)
user_input.grid(row=0, column=1)

convert_button = Button(win, text="Convert", height=1, width=10, command=convert_kg)
convert_button.grid(row=0, column=2)

gram_label = StringVar()
gram_text = Label(win, height=1, width=20, textvariable=gram_label)
gram_text.grid(row=1, column=0)


pound_label = StringVar()
pound_text = Label(win, height=1, width=20, textvariable=pound_label)
pound_text.grid(row=1, column=1)

ounce_label = StringVar()
ounce_text = Label(win, height=1, width=20, textvariable=ounce_label)
ounce_text.grid(row=1, column=2)

win.mainloop()

This is how it looks like: