python - tkinter button press to function call -

hey guys first post , not hi. anyway trying make scientific calculator tkinter , im not it(and python second proper assignment). anyway of code wrong im trying take 1 step @ time in particular im concerned function add. im calling via button want pass function +. in turn creating array can calculate from. keeps erroring , dont know how fix it. annoying me if out appreciated

from tkinter import* operator import*  class app:     def __init__(self,master):#is master button widgets         frame=frame(master)         frame.pack()         self.addition = button(frame, text="+", command=self.add)#when clicked sends call +         self.addition.pack()     def add(y):         do("+")     def do(x):#will colaborate of inputs         cont, = true, 0         store=["+","1","+","2","3","4"]         in range(5):             x=store[0+i]             print(store[0+i])             cont = false         if cont == false:             print(eval_binary_expr(*(store[:].split())))     def get_operator_fn(op):#allows array split find operators         return {             '+' : add,             '-' : sub,             '*' : mul,             '/' : truediv,             }[op]     def eval_binary_expr(op1, num1, op2, num2):         store[1],store[3] = int(num1), int(num2)         return get_operator_fn(op2)(num1, num2)   root=tk() app=app(root) root.mainloop()#runs programme 

generally speaking, every method in class should take self first argument. name self convention. not keyword in python. however, when call method such obj.add(...), first argument sent method instance obj. convention call instance self in method definition. methods need modified include self first argument:

class app:     def __init__(self, master):#is master button widgets         frame=frame(master)         frame.pack()         self.addition = button(frame, text="+", command=self.add)#when clicked sends call +         self.addition.pack()     def add(self):         self.do("+")     def do(self, x):         ... 

note when call self.do("+"), inside method do, x bound "+". later on in method see

x=store[0+i] 

which rebind x value store[i]. don't know trying here, aware doing means you've lost "+" value passed in.