Answer:
from tkinter import *
expression = ""
def press(num):
global expression
expression = expression + str(num)
equation.set(expression)
def equalpress():
try:
global expression
total = str(eval(expression))
equation.set(total)
expression = ""
except:
equation.set(" error ")
expression = ""
def clear():
global expression
expression = ""
equation.set("")
if __name__ == "__main__":
gui = Tk()
equation = StringVar(gui, "")
equation.set("")
gui.geometry("270x150")
expression_field = Entry(gui, textvariable=equation)
expression_field.grid(columnspan=4, ipadx=70)
buttonl = Button(gui, text=' 1', fg='black', bg='white',command=lambda: press(1), height=1, width=7)
buttonl.grid(row=2, column=0)
button2 = Button(gui, text=' 2', fg='black', bg='white',command=lambda: press(2), height=1, width=7)
button2.grid(row=2, column=1)
button3 = Button(gui, text=' 3', fg='black', bg='white',command=lambda: press(3), height=1, width=7)
button3.grid(row=2, column=2)
button4 = Button(gui, text=' 4', fg='black', bg='white',command=lambda: press(4), height=1, width=7)
button4.grid(row=3, column=0)
button5 = Button(gui, text=' 5', fg='black', bg='white',command=lambda: press(5), height=1, width=7)
button5.grid(row=3, column=1)
button6 = Button(gui, text=' 6', fg='black', bg='white',command=lambda: press(6), height=1, width=7)
button6.grid(row=3, column=2)
button7 = Button(gui, text=' 7', fg='black', bg='white',command=lambda: press(7), height=1, width=7)
button7.grid(row=4, column=0)
button8 = Button(gui, text=' 8', fg='black', bg='white',command=lambda: press(8), height=1, width=7)
button8.grid(row=4, column=1)
button9 = Button(gui, text=' 9', fg='black', bg='white',command=lambda: press(9), height=1, width=7)
button9.grid(row=4, column=2)
button0 = Button(gui, text=' 0', fg='black', bg='white',command=lambda: press(2), height=1, width=7)
button0.grid(row=5, column=0)
Add = Button(gui, text=' +', fg='black', bg='white',command=lambda: press("+"), height=1, width=7)
Add.grid(row=2, column=3)
Sub = Button(gui, text=' -', fg='black', bg='white',command=lambda: press("-"), height=1, width=7)
Sub.grid(row=3, column=3)
Div = Button(gui, text=' /', fg='black', bg='white',command=lambda: press("/"), height=1, width=7)
Div.grid(row=5, column=3)
Mul = Button(gui, text=' *', fg='black', bg='white',command=lambda: press("*"), height=1, width=7)
Mul.grid(row=4, column=3)
Equal = Button(gui, text=' =', fg='black', bg='white',command=equalpress, height=1, width=7)
Equal.grid(row=5, column=2)
Clear = Button(gui, text=' Clear', fg='black', bg='white',command=clear, height=1, width=7)
Clear.grid(row=5, column=1)
Decimal = Button(gui, text=' .', fg='black', bg='white',command=lambda: press("."), height=1, width=7)
Decimal.grid(row=6, column=0)
gui.mainloop()
Explanation:
I fixed several other typos. Your calculator works like a charm!