I've gathered numbers in a configuration file, and I would like to apply them to buttons. Clicking the button should allow the number to be changed and then re-written to the config file. My current code is as follows:

from tkinter import*
import tkinter as tk
import tkinter.simpledialogdef onChange(i):     btn_list[i].config(text='Updating...',bg='red')  btn_list[i].grid(in_=root,row=rw[i],column=2)ans=tk.simpledialog.askfloat('Updating....', 'What is the current price?')if ans:btn_list[i].config(text='RM {:,.2f}'.format(ans))btn_list[i].config(bg='yellow')c=str(ans)fw=open('dataUpdate.txt','w')fw.write(c)fw.close()root=Tk()Title=['Item','Unit','Price']
Item=['Kopi O','Teh O','Teh Tarik']
Unit= '1 cup'
cl=[0,1,2]
rw=[1,2,3]
btn_list=[]
fr=open('dataUpdate.txt','r')with open('dataUpdate.txt') as input_file:text=input_file.read()strings=text.split()number=[float(item) for item in strings]print(number)fr.close()for k in range(3):btnT1=tk.Button(root,text=Title[k],width=12,bg='light green')btnT1.grid(in_=root,row=0,column=cl[k])for x in range(3):btnT2=tk.Button(root,text=Item[x],width=12)btnT2.grid(in_=root,row=rw[x],column=0)for y in range(3):btnT3=tk.Button(root,text=Unit,width=12)btnT3.grid(in_=root,row=rw[y],column=1)             for z in range(3):btnT4=tk.Button(root,text=('RM {:,.2f}'.format(number[z])),bg='yellow',width=12,\command=lambda i=z:onChange(i))btnT4.grid(in_=root,row=rw[z],column=2)btn_list.append(btnT4)root.mainloop()

Here's a screenshot of my basic configuration file:

Try this simple example:

from tkinter import*
import tkinter as tk
import tkinter.simpledialog
import configparser
import os.pathdef onChange(i):     btn_list[i].config(text='Updating...',bg='red')  btn_list[i].grid(in_=root,row=rw[i],column=2)ans=tk.simpledialog.askfloat('Updating....', 'What is the current price?')if ans:btn_list[i].config(text='RM {:,.2f}'.format(ans))btn_list[i].config(bg='yellow')c=str(ans)#fw=open('dataUpdate.txt','w')#fw.write(c)#fw.close()#----------------------------------------------# Here you can call update(section, key value) update('Section1', 'number%s' % i, c)#----------------------------------------------root=Tk()Title=['Item','Unit','Price']
Item=['Kopi O','Teh O','Teh Tarik']
Unit= '1 cup'
cl=[0,1,2]
rw=[1,2,3]
btn_list=[]#------------------------------------------------------------------------
config = configparser.RawConfigParser()def init():'Create a configuration file if does not exist'config.add_section('Section1')config.set('Section1', 'number1', '1')config.set('Section1', 'number2', '0.8')config.set('Section1', 'number3', '0.2')with open('dataUpdate.cfg', 'w') as output:config.write(output)#------------------------------------------------------------------------
# check if dataUpdate.cfg exist if not create it   
if not os.path.exists('dataUpdate.cfg'):init()# Read configurations using section and key to get the value
config.read('dataUpdate.cfg')
number = [config.getfloat('Section1', 'number%s' % (i)) for i in range(3)]
#------------------------------------------------------------------------#------------------------------------------------------------
def update(section, key, value):#Update config using section key and the value to change#call this when you want to update a value in configuation file# with some changes you can save many values in many sectionsconfig.set(section, key, value )with open('dataUpdate.cfg', 'w') as output:config.write(output)
#------------------------------------------------------------for k in range(3):btnT1=tk.Button(root,text=Title[k],width=12,bg='light green')btnT1.grid(in_=root,row=0,column=cl[k])for x in range(3):btnT2=tk.Button(root,text=Item[x],width=12)btnT2.grid(in_=root,row=rw[x],column=0)for y in range(3):btnT3=tk.Button(root,text=Unit,width=12)btnT3.grid(in_=root,row=rw[y],column=1)             for z in range(3):btnT4=tk.Button(root,text=('RM {:,.2f}'.format(number[z])),bg='yellow',width=12,\command=lambda i=z:onChange(i))btnT4.grid(in_=root,row=rw[z],column=2)btn_list.append(btnT4)root.mainloop()