Tkinter Calculator

# question: https://stackoverflow.com/questions/60216042/problem-with-button-alignment-with-python-tkinter
# image: https://imgur.com/gallery/AS5JsPQ

import tkinter as tk

# --- functions ---

def on_click(value):
    result['text'] += value

# --- main ---

window = tk.Tk()
window.geometry("800x600")
window.title("Calculator")

menu = tk.Menu(window)
new_item = tk.Menu(menu)
new_item.add_command(label="Language", command=window.destroy)
new_item.add_command(label="Reset", command=window.destroy)
new_item.add_command(label="Save result as txt", command=window.destroy)
new_item.add_command(label="Help", command=window.destroy)
new_item.add_command(label="Quit", command=window.destroy)
menu.add_cascade(label="Options", menu=new_item)
window.config(menu=menu)

# ---

for c in range(1, 5):
    window.columnconfigure(c, weight=1)

for r in range(1, 6):
    window.rowconfigure(r, weight=1)

window['bg'] = 'black'
grid_options = {'sticky': 'news', 'padx': 1, 'pady': 1}

# --- result ---

frame_result = tk.Frame(window, bg='red')
frame_result.grid(column=1, row=1, columnspan=4, **grid_options)

result = tk.Label(frame_result, text="", bg="yellow", fg="black", cursor="exchange")
result.pack(padx=20, pady=(20,20), fill='both', expand=True) # , pady=(20,70)

# --- numbers ---

options = {'bg': "green", 'activebackground': "darkgreen", 'fg': "white", 'relief': 'flat', 'highlightbackground': 'green'}#, 'highlightthickness': 0}

# -
btn = tk.Button(window, text="7", command=lambda:on_click('7'), **options)
btn.grid(column=1, row=2, **grid_options)

btn = tk.Button(window, text="8", command=lambda:on_click('8'), **options)
btn.grid(column=2, row=2, **grid_options)

btn = tk.Button(window, text="9", command=lambda:on_click('9'), **options)
btn.grid(column=3, row=2, **grid_options)

# -

btn = tk.Button(window, text="4", command=lambda:on_click('4'), **options)
btn.grid(column=1, row=3, **grid_options)

btn = tk.Button(window, text="5", command=lambda:on_click('5'), **options)
btn.grid(column=2, row=3, **grid_options)

btn = tk.Button(window, text="6", command=lambda:on_click('6'), **options)
btn.grid(column=3, row=3, **grid_options)

# -

btn = tk.Button(window, text="1", command=lambda:on_click('1'), **options)
btn.grid(column=1, row=4, **grid_options)

btn = tk.Button(window, text="2", command=lambda:on_click('2'), **options)
btn.grid(column=2, row=4, **grid_options)

btn = tk.Button(window, text="3", command=lambda:on_click('3'), **options)
btn.grid(column=3, row=4, **grid_options)

# -

btn = tk.Button(window, text="0", command=lambda:on_click('0'), **options)
btn.grid(column=1, row=5, **grid_options)

options =  {'fg': "white", 'relief': 'flat'}#, 'highlightthickness': 0}

btn = tk.Button(window, text=",", command=lambda:on_click(','), bg="green", activebackground="darkgreen", highlightbackground='green', **options)
btn.grid(column=2, row=5, **grid_options)

options =  {'fg': "black", 'relief': 'flat'}#, 'highlightthickness': 0}

btn = tk.Button(window, text="=", command=lambda:on_click('='), bg="yellow", activebackground="orange", highlightbackground='yellow', **options)
btn.grid(column=3, row=5, **grid_options)

# --- other ---

options = {'bg': "lightgreen", 'activebackground': "lightblue", 'fg': "black", 'relief': 'flat', 'highlightthickness': 0}

btn = tk.Button(window, text="+", command=lambda:on_click('+'), **options)
btn.grid(column=4, row=2, **grid_options)

btn = tk.Button(window, text="-", command=lambda:on_click('-'), **options)
btn.grid(column=4, row=3, **grid_options)

btn = tk.Button(window, text="*", command=lambda:on_click('*'), **options)
btn.grid(column=4, row=4, **grid_options)

btn = tk.Button(window, text="/", command=lambda:on_click('/'), **options)
btn.grid(column=4, row=5, **grid_options)

# ---

window.mainloop()