set stringvar entry code example
Example 1: read value from entry tkinter
#ent is the name of the Entry
s = ent.get()
Example 2: write in entry() in tkinter
from Tkinter import *
master = Tk()
e = Entry(master)
e.pack()
e.focus_set()
def callback():
print e.get()
b = Button(master, text="get", width=10, command=callback)
b.pack()
mainloop()