Python- Real Time Stock Price plot with matplotlib- figure won't show

Question

I'm trying to make a graph that plots real time stock prices from yahoo finance using matplotlib and python 3.5. My code is as follows:

import urllib.request
from bs4 import BeautifulSoup
import matplotlib.pyplot as plt
import datetime
import time

t = urllib.request.urlopen('http://finance.yahoo.com/quote/YHOO/history?ltr=1')
the = t.read()
soup = BeautifulSoup(the, 'html.parser')
timeticks = []
x = []
prices = []
i = 1

while 1:    

    n = soup.find('span',class_="Fw(500) D(ib) Fz(42px)")     
    time.sleep(1)
    plt.cla()
    nf = float(n.string)
    prices.append(nf)

    now= datetime.datetime.now()
    times=('%02d:%02d:%d'%(now.hour,now.minute,now.second))
    timeticks.append(times)
    x.append(i)

    print(timeticks)
    print(x)
    print(prices)

    plt.xticks(x,timeticks)
    plt.plot(x,prices,"b-")
    plt.xlabel("Time")
    plt.ylabel("Stock prices")
    plt.title("Yahoo's Stocks")
    plt.show()
    i +=1

I know that some of the code might seem wrong(I am still learning).

When I ran this code, the plot doesn't show up. I added print statements to check if the lists were working and they were.

    print(timeticks)
    print(x)
    print(prices)

So what do I need to do to make my code working? Thank You