Calculator_App.py

from tkinter import Tk,END,Entry,N,E,S,W,Button
from tkinter import font
from tkinter import Label
from functools import partial

def get_input(entry,argu):
    entry.insert(END,argu)

def backspace(entry):
    input_len = len(entry.get())
    entry.delete(input_len - 1)

def clear(entry):
    entry.delete(0,END)

def calc(entry):
    input_info = entry.get()
    try:
        output = str(eval(input_info.strip()))
    except ZeroDvivisionError:
        popupmsg()
        output = ""
    clear(entry)
    entry.insert(END,output)

def popupmsg():
    popup = Tk()
    popup.resizable(0,0)
    popup.geometry("120x100")
    popup.title("Alert")
    label = Label(popup,text="Cannot divide by 0! \n Enter valid values")
    label.pack(side="top",fill="x",pady=10)
    B1 = Button(popup,text="Okay",bg="#DDDDDD",command=popup.destory)
    B1.pack()

def cal():
    root = Tk()
    root.title("Calc")
    root.resizable(0,0)

    entry_font = font.Font(size=15)
    entry=Entry(root,justify="right",font=entry_font)
    entry.grid(row=0,column=0,columnspan=4,sticky=N + W + S + E, padx=5,pady=5)
    cal_button_bg = '#FF6600'
    num_button_bg = '#4B4B4B'
    other_button_bg = '#DDDDDD'
    text_fg = '#FFFFFF'
    button_active_bg = '#C0C0C0'

    num_button = partial(Button,root,fg=text_fg,bg=num_button_bg,padx=10,pady=3,activebackground=button_active_bg)
    cal_button = partial(Button,root,fg=text_fg,bg=cal_button_bg,padx=10,pady=3,activebackground=button_active_bg)

    button7 = num_button(text='7',bg=num_button_bg,command=lambda:get_input(entry,'7'))
    button7.grid(row=2,column=0,pady=5)

    button8 = num_button(text='8',command=lambda:get_input(entry,'8'))
    button8.grid(row=2,column=1,pady=5)

    button9 = num_button(text='9',command=lambda:get_input(entry,'9'))
    button9.grid(row=2,column=2,pady=5)

    button10 = cal_button(text='+',command=lambda:get_input(entry,'+'))
    button10.grid(row=4,column=3,pady=5)
    
    button4 = num_button(text='4',command=lambda:get_input(entry,'4'))
    button4.grid(row=3,column=0,pady=5)

    button5 = num_button(text='5',command=lambda:get_input(entry,'5'))
    button5,grid(row=3,column=1,pady=5)

    button6 = num_button(text='6',command=lambda:get_input(entry,'6'))
    button6.grid(row=3,column=2,pady=5)

    button11 = cal_button(text='-',command=lambda:get_input(entry,'-'))
    button11.grid(row=3,column=3,pady=5)

    button1 = num_button(text='1',command = lambd:get_input(entry,'1'))
    button1.grid(row=4,column=0,pady=5)

    button2 = num_button(text='2', command=lambda:get_input(entry,'2'))
    button2.grid(row=4,column=1,pady=5)

    button3 = num_button(text='3',command=lambda:get_input(entry,'3'))
    button3.grid(row=4,column=2,pady=5)

    button12 = cal_button(text='*',command=lambda:get_input(entry,'*'))
    button12.grid(row=2,column=3,pady=5)

    button0 = num_button(text='0',command=lambda:get_input(entry,'0'))
    button0.grid(row=5,column=0,pady=5)

    button13 = num_button(text='.',command=lambda:get_input(entry,'.'))
    button13.grid(row=5,column=1,pady=5)

    button14=Button(root,text='/',fg=text_fg,bg=cal_button_bg,padx=10,pady=3,command=lambda:get_input(entry,'/'))
    button14.grid(row=1,column=3,pady=5)

    button15 = Button(root,text='<-',bg=other_button_bg,padx=10,pady=3,command=lambda:backspace(entry),activebackground=button_active_bg)
    button15.grid(row=1,column=0,columnspan=2,padx=3,pady=5,sticky=N+S+E+W)

    button16 = Button(root,text='C',bg=other_button_bg,padx=10,pady=3,command=lambda:clear(entry),activebackground=button_active_bg)
    button16.grid(row=1,column=2,pady=5)
    button17 = Button(root,text='=',fg=text_fg,bg=cal_button_bg,padx=10,pady=3,command=lambda:calc(entry),activebackground=button_active_bg)
    button17.grid(row=5,column=3,pady=5)

    button18 = Button(root,text='^',fg=text_fg,bg=cal_button_bg,padx=10,pady=3,command=lambda:get_input(entry,'**'))
    button18.grid(row=5,column=2,pady=5)

    root.mainloop()

if __name__ == '__main__':
    cal()