Entry Widget issue

[PA3040]

Sorry I could not update the modified code

import serial
from tkinter import *
import matplotlib.pyplot as plt
from drawnow import *

values = []
root = Tk()
plt.ion()
cnt=0
var = StringVar()
serialArduino = serial.Serial('COM3',baudrate = 9600, timeout = 1)
root.title("D Cube Serial Read")
e = Entry(root,width = 35, textvariable = var ,borderwidth = 5)
e.grid(row = 0, column = 0, columnspan = 3,padx = 10,pady = 10)

def plotValues():
     plt.legend(loc='upper right')
    
while True:
    while (serialArduino.inWaiting()==0):
        pass
    valueRead = serialArduino.readline()
    print(valueRead)

    #check if valid value can be casted
    try:
        valueInInt = int(valueRead)
        print(valueInInt)
        e.delete(0,END)
        #e.insert(1,valueInInt)
        var.set(valueInInt)
        #drawnow(plotValues)
                
           
    except ValueError:
        print ("Invalid! cannot cast")

as you can see the I commented the following line then widgets does not open but on the python shell values are displayed

#drawnow(plotValues)