DISCLAIMER: I'm still putzing around with Python, so don't take my answers as gospel.
You could do something like this...
from Tkinter import *
root = Tk()
master = Frame(root)
e = Entry(master)
answer = ""
answer = e.get()
b1 = Button(master, text="SET", width=10, command=setanswer)
b2 = Button(master, text="PRINT", width=10, command=printanswer)
I set the answer variable as a blank string, then in the functions, I called the global answer variable. It jumps the namespace barrier to get the higher-up variable.
In my modification, the setanswer function sets the variable to whatever is typed into the entry box. The printanswer function prints what is in the answer variable. You can type something new into the entry box, but until you click SET, the variable doesn't change.
I also set master to a frame, and got rid of parent. You were creating three root windows with the three "= Tk()" lines.
Python normal ends a print command with a newline, unless you append a comma at the end...
You can also format your print line, something like...
print 'The answer is "%s".' % answer