title: AttributeError: 'dict' object has no attribute 'plot'
body: <pre><code>from iexfinance import Stock
  import matplotlib.pyplot as plt
  tsla = Stock('TSLA')
  tsla.get_close()
  tsla.get_price()
  
  from iexfinance import get_historical_data
  from datetime import datetime
  import pandas as pd
  pd.set_option('display.max_rows', 1000)
  
  start = datetime(2017, 2, 9)
  end = datetime(2017, 5, 24)
  
  df = get_historical_data("TSLA", start=start, end=end, output_format='json')
  df.plot()
  plt.show()
  
  
  ---------------------------------------------------------------------------
  AttributeError                            Traceback (most recent call 
  last)
  &lt;ipython-input-16-77b5455be846&gt; in &lt;module&gt;()
        8 
        9 df = get_historical_data("TSLA", start=start, end=end, 
  output_format='json')
  ---&gt; 10 df.plot()
       11 plt.show()
       12 df
  
  AttributeError: 'dict' object has no attribute 'plot'
  </code></pre>
  
  <p>I am trying to get the plot for the dataframe created with the different prices from the start and end date. I tried reading different blogs but none seem to solve it. I am sure I am making a very basic error. Although, I am not able to figure out what am I doing wrong here, any suggestions to fix it?</p>