ValueError when plotting lists using matplotlib (x and y must have same first dimension)

Question

I'm trying to create a live sentiment analysis graph for tweets. The program loads the data from a locally stored JSON file and converts the "created_at" data to unix time while using VaderSentiment to analyse the text and update a running total of sentiment.

fig = plt.figure()
ax1 = fig.add_subplot(1, 1, 1)

yar = []
total = []
created = []
sid = SentimentIntensityAnalyzer()
#ss = sid.polarity_scores(sentence)


def animate(i):

  compound_total = 0

  with open('python.json', 'r') as f:

    line = f.readline()
    for line in f:
      tweet = json.loads(line)
      #print(sid.polarity_scores(tweet['text']))
      total.append(sid.polarity_scores(tweet['text'])['compound'])
      created_at = tweet['created_at']
      tweet_time = time.mktime(time.strptime(created_at,"%a %b %d %H:%M:%S +0000 %Y"))
      created.append(tweet_time)


    for each in total:
      compound_total += each

    yar.append(compound_total)
    print (yar[len(yar)-1], ", ", created[len(created)-1])

    ax1.clear()
    ax1.plot(created, yar, 'bo')
    #plt.plot(np.unique(xar), np.poly1d(np.polyfit(xar, yar, 1))(np.unique(xar)))

ani = animation.FuncAnimation(fig, animate, interval=1000)
plt.show()

The data is stored in standard python lists. I think the lists are the same length, the error suggests otherwise.

Can anyone suggest a solution/reason the lists are different sizes?

PS: Strangely the program returns the first pair of co-ordinates to the system before throwing the error

Also sorry for anything stupid - I'm not good at this