title: Pandas_datareader error SymbolWarning: Failed to read symbol: 'T', replacing with NaN
body: <p>I have this code which gets a list of symbols from wikipedia and then gets the stock data from yahoofinance. This is a simple code which was working fine up till a couple days ago but for some reason i getting the <code>unable to read symbol</code> error on many stocks. Is yahoo doing this? What can i do to fix this error. I cannot ignore this because over 50 symbols were NaN and when i rerun the code different symbols show up in the error</p>
  
  <p>pandas_datareader version: 0.8.1
  Code:</p>
  
  <pre><code>import datetime
  import pandas as pd
  import numpy as np
  import csv
  from pandas_datareader import data as web
  import matplotlib
  import matplotlib.pyplot as plt
  import requests
  import bs4 as bs
  from urllib.request import urlopen
  from bs4 import BeautifulSoup
  import tqdm
  from pandas import DataFrame
  import seaborn as sns
  
  resp = requests.get('http://en.wikipedia.org/wiki/List_of_S%26P_500_companies')
  soup = bs.BeautifulSoup(resp.text, 'lxml')
  table = soup.find('table', {'class': 'wikitable sortable'})
  tickers = []
  for row in table.findAll('tr')[1:]:
      ticker = row.findAll('td')[0].text.strip()
      tickers.append(ticker)
  
  start = datetime.date(2008,11,1)
  end = datetime.date.today()
  # df = web.get_data_yahoo(tickers, start, end)
  df = web.DataReader(tickers, 'yahoo', start, end)
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>C:\ProgramData\Anaconda3\lib\site-packages\pandas_datareader\base.py:270: SymbolWarning: Failed to read symbol: 'T', replacing with NaN.
    warnings.warn(msg.format(sym), SymbolWarning)
  C:\ProgramData\Anaconda3\lib\site-packages\pandas_datareader\base.py:270: SymbolWarning: Failed to read symbol: 'BKR', replacing with NaN.
    warnings.warn(msg.format(sym), SymbolWarning)
  C:\ProgramData\Anaconda3\lib\site-packages\pandas_datareader\base.py:270: SymbolWarning: Failed to read symbol: 'BRK.B', replacing with NaN.
    warnings.warn(msg.format(sym), SymbolWarning)
  </code></pre>