calculater.py

from tkinter import *


def iCalc(source, side):
    storeobj = Frame(source, borderwidth=5, bd=3, bg="light blue")
    storeobj.pack(side=side, expand=YES, fill=BOTH)
    return storeobj


def button(source, side, text, command=None):
    storeobj = Button(source, text=text, command=command)
    storeobj.pack(side=side, expand=YES, fill=BOTH)
    return storeobj


class app(Frame):
    def __init__(self):
        Frame.__init__(self)
        self.option_add('*Font', 'arial 25 bold')
        self.pack(expand=YES, fill=BOTH)
        self.master.title('My calculator')

        display = StringVar()
        Entry(self, relief=RIDGE,
              textvariable=display, justify='right', bd=30, bg="pink").pack(side=TOP, expand=YES,
                                                                              fill=BOTH)

        for clearBut in (["CE"], ["C"]):
            erase = iCalc(self, TOP)
            for ichar in clearBut:
                button(erase, LEFT, ichar,
                       lambda storeObj=display, q=ichar: storeObj.set(''))

        for NumBut in ("#@%!^", "789*/", "456+-", "123()", "0.{}√"):
            FunctionNum = iCalc(self, TOP)
            for iEquals in NumBut:
                button(FunctionNum, LEFT, iEquals,
                       lambda storeObj=display, q=iEquals: storeObj.set(storeObj.get() + q))
        EqualsButton = iCalc(self, TOP)
        for iEquals in "=":
            if iEquals == '=':
                btniEquals = button(EqualsButton, LEFT, iEquals)
                btniEquals.bind('<ButtonRelease-1>',
                                lambda e, s=self, storeObj=display: s.calc(storeObj), '+')
            else:
                btniEquals = button(EqualsButton, LEFT, iEquals,
                                    lambda storeObj=display, s=' %s ' % iEquals: storeObj.set(storeObj.get() + s))

    def calc(self, display):
        try:
            display.set(eval(display.get()))
        except:
            display.set("ERROR")


if __name__ == '__main__':
    app().mainloop()