##Имопртируемые модули
from tkinter import *
import math

##Окно калькулятора
tk = Tk()
tk.title('Простой калькулятор')
tk.resizable(0,0)

##Поле ввода
operator = ''
text = StringVar()
calculator_entry = Entry(tk, font = ('arial', 20, 'bold'), justify = 'right', textvariable = text, width = 32, bd = 3)
calculator_entry.grid(row = 0, column = 0, columnspan = 6)
calculator_entry.insert(0, '0')

##Логика калькулятора
def btnClick(numbers):
    global operator
    if text == 0:
        operator = ''
    operator = operator + str(numbers)
    text.set(operator)
def btnClear():
    global operator
    operator = ''
    text.set('0')
def btnEquals():
    try:
        global operator
        sumup = str(eval(operator))
        text.set(sumup)
        operator = sumup
    except:
        text.set('Ошибка!')

##Кнопки калькулятора
btn7 = Button(tk, text = '7', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(7)).grid(column = 0, row = 1)
btn8 = Button(tk, text = '8', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(8)).grid(column = 1, row = 1)
btn9 = Button(tk, text = '9', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(9)).grid(column = 2, row = 1)
btnplus = Button(tk, text = '+', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('+')).grid(column = 3, row = 1)
btndegree = Button(tk, text = 'x²', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('x²')).grid(column = 4, row = 1)
btnplusandminus = Button(tk, text = '±', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('±')).grid(column = 5, row = 1)
btn4 = Button(tk, text = '4', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(4)).grid(column = 0, row = 2)
btn5 = Button(tk, text = '5', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(5)).grid(column = 1, row = 2)
btn6 = Button(tk, text = '6', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(6)).grid(column = 2, row = 2)
btnminus = Button(tk, text = '-', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('-')).grid(column = 3, row = 2)
btnradical = Button(tk, text = '√', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('√')).grid(column = 4, row = 2)
btn7percent = Button(tk, text = '%', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('%')).grid(column = 5, row = 2)
btn1 = Button(tk, text = '1', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(1)).grid(column = 0, row = 3)
btn2 = Button(tk, text = '2', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(2)).grid(column = 1, row = 3)
btn3 = Button(tk, text = '3', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(3)).grid(column = 2, row = 3)
btnmultiplication = Button(tk, text = '*', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('*')).grid(column = 3, row = 3)
btnopenbracket = Button(tk, text = '(', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('(')).grid(column = 4, row = 3)
btnbackspace = Button(tk, text = '⌫', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('⌫')).grid(column = 5, row = 3)
btnclear = Button(tk, text = 'C', font = ('arial', 15, 'bold'), width = 6, height = 3, command = btnClear).grid(column = 0, row = 4)
btn0 = Button(tk, text = '0', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(0)).grid(column = 1, row = 4)
btnpoint = Button(tk, text = '.', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('.')).grid(column = 2, row = 4)
btndivision = Button(tk, text = '÷', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick('÷')).grid(column = 3, row = 4)         ###
btnclosebracket = Button(tk, text = ')', font = ('arial', 15, 'bold'), width = 6, height = 3, command = lambda:btnClick(')')).grid(column = 4, row = 4)
btneval = Button(tk, text = '=', font = ('arial', 15, 'bold'), width = 6, height = 3, command = btnEquals).grid(column = 5, row = 4)

##Цикл обработки событий
tk.mainloop()