Sum of Combobox & Text widget inputs

Adding combobox with selection options

sel1=tk.IntVar() # string variable 
sel1.set(0)
data=[5,3,15,22]
cb1 = ttk.Combobox(my_w, values=data,height=3, width=5,
    font=22, textvariable=sel1)
cb1.grid(row=0,column=0,padx=10,pady=30)

On click of the button

b1=tk.Button(my_w,text='Sum',command=lambda:my_upd(),font=22)

Reading and adding values

def my_upd(*args):
    total=sel1.get() + int(t1.get("1.0",END))
    l1.config(text=total)# update the Label text 

import tkinter as tk
from tkinter import ttk
from tkinter import *
my_w = tk.Tk()
my_w.geometry("400x250")  # Size of the window 
my_w.title("www.plus2net.com")  # Adding a title
def my_upd(*args):
    total=sel1.get() + int(t1.get("1.0",END))
    l1.config(text=total) # update the Label text 

sel1=tk.IntVar() # string variable 
sel1.set(0)
data=[5,3,15,22]
cb1 = ttk.Combobox(my_w, values=data,height=3, 
	width=5,font=22, textvariable=sel1)
cb1.grid(row=0,column=0,padx=10,pady=10)
t1=tk.Text(my_w,width=10,height=1,bg='yellow',font=22)
t1.grid(row=0,column=1,padx=5)
t1.insert(tk.END, 0) # initial value of text widget 
l1=tk.Label(my_w,text='Total',font=22,fg='blue')
l1.grid(row=0,column=2,padx=5)
b1=tk.Button(my_w,text='Sum',command=lambda:my_upd(),font=22)
b1.grid(row=1,column=1)
#sel1.trace('w',my_upd) # to trigger the function on change 
my_w.mainloop()  # Keep the window open