Try to workaround Yahoo! finance 404 errors, better error messages
randomly get this crap

```

import pandas
import pandas.io.data as pd

def get_close(ticker, start, end):

    stock = pd.DataReader(ticker, 'yahoo', start, end)
    adj_close = stock['Adj Close']

    return adj_close[-1]


start = datetime.datetime(2010,1,1)
end = datetime.datetime(2012,1,24)
ticker = ['TLT', 'IEF', 'IYR', 'XLY', 'XLK', 'XLU', 'XLV', 'XLP', 'XLI', 'XLF', 'XLB', 'XLE', 'SPY', 'EFA', 'EEM', 'EWJ', 'IWM', 'QQQ', 'LQD', 'JNK']

for t in ticker:
    result = get_close(t, start, end)
    print t,result
## -- End pasted text --
TLT 116.17
IEF 104.15
IYR 59.52
XLY 41.25
XLK 26.87
XLU 34.47
---------------------------------------------------------------------------
Exception                                 Traceback (most recent call last)
/home/wesm/code/pandas/<ipython-input-7-eb9190ce71e6> in <module>()
     17 
     18 for t in ticker:
---> 19     result = get_close(t, start, end)
     20     print t,result

/home/wesm/code/pandas/<ipython-input-7-eb9190ce71e6> in get_close(ticker, start, end)
      6 def get_close(ticker, start, end):
      7 
----> 8     stock = pd.DataReader(ticker, 'yahoo', start, end)
      9     adj_close = stock['Adj Close']
     10 

/home/wesm/code/pandas/pandas/io/data.pyc in DataReader(name, data_source, start, end)
     51 
     52     if(data_source == "yahoo"):
---> 53         return get_data_yahoo(name=name, start=start, end=end)
     54     elif(data_source == "fred"):
     55         return get_data_fred(name=name, start=start, end=end)

/home/wesm/code/pandas/pandas/io/data.pyc in get_data_yahoo(name, start, end)
    133 
    134     lines = urllib.urlopen(url).read()
--> 135     return read_csv(StringIO(lines), index_col=0, parse_dates=True)[::-1]
    136 
    137 def get_data_fred(name=None, start=dt.datetime(2010, 1, 1),

/home/wesm/code/pandas/pandas/io/parsers.pyc in read_csv(filepath_or_buffer, sep, header, index_col, names, skiprows, na_values, parse_dates, date_parser, nrows, iterator, chunksize, skip_footer, converters, verbose, delimiter, encoding)
    125         return parser
    126 
--> 127     return parser.get_chunk()
    128 
    129 @Appender(_read_table_doc)

/home/wesm/code/pandas/pandas/io/parsers.pyc in get_chunk(self, rows)
    483 
    484         if len(self.columns) != len(zipped_content):
--> 485             raise Exception('wrong number of columns')
    486 
    487         data = dict((k, v) for k, v in izip(self.columns, zipped_content))

Exception: wrong number of columns

In [8]: %debug
> /home/wesm/code/pandas/pandas/io/parsers.py(485)get_chunk()
    484         if len(self.columns) != len(zipped_content):
--> 485             raise Exception('wrong number of columns')
    486 

ipdb> u
> /home/wesm/code/pandas/pandas/io/parsers.py(127)read_csv()
    126 
--> 127     return parser.get_chunk()
    128 

ipdb> 
> /home/wesm/code/pandas/pandas/io/data.py(135)get_data_yahoo()
    134     lines = urllib.urlopen(url).read()
--> 135     return read_csv(StringIO(lines), index_col=0, parse_dates=True)[::-1]
    136 

ipdb> lines
'<!doctype html public "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">\n<html><head><title>Yahoo! - 404 Not Found</title><style>\n/* nn4 hide */ \n/*/*/\nbody {font:small/1.2em arial,helvetica,clean,sans-serif;font:x-small;text-align:center;}table {font-size:inherit;font:x-small;}\nhtml>body {font:83%/1.2em arial,helvetica,clean,sans-serif;}input {font-size:100%;vertical-align:middle;}p, form {margin:0;padding:0;}\np {padding-bottom:6px;margin-bottom:10px;}#doc {width:48.5em;margin:0 auto;border:1px solid #fff;text-align:center;}#ygma {text-align:right;margin-bottom:53px}\n#ygma img {float:left;}#ygma div {border-bottom:1px solid #ccc;padding-bottom:8px;margin-left:152px;}#bd {clear:both;text-align:left;width:75%;margin:0 auto 20px;}\nh1 {font-size:135%;text-align:center;margin:0 0 15px;}legend {display:none;}fieldset {border:0 solid #fff;padding:.8em 0 .8em 4.5em;}\nform {position:relative;background:#eee;margin-bottom:15px;border:1px solid #ccc;border-width:1px 0;}\n#s1p {width:15em;margin-right:.1em;}\nform span {position:absolute;left:70%;top:.8em;}form a {font:78%/1.2em arial;display:block;padding-left:.8em;white-space:nowrap;background: url(http://l.yimg.com/a/i/s/bullet.gif) no-repeat left center;} \nform .sep {display:none;}.more {text-align:center;}#ft {padding-top:10px;border-top:1px solid #999;}#ft p {text-align:center;font:78% arial;}\n/* end nn4 hide */\n</style></head>\n<body><div id="doc">\n<div id="ygma"><a href="http://us.rd.yahoo.com/404/*http://www.yahoo.com"><img\nsrc=http://l.yimg.com/a/i/yahoo.gif\nwidth=147 height=31 border=0 alt="Yahoo!"></a><div><a\nhref="http://us.rd.yahoo.com/404/*http://www.yahoo.com">Yahoo!</a>\n - <a href="http://us.rd.yahoo.com/404/*http://help.yahoo.com">Help</a></div></div>\n<div id="bd"><h1>Sorry, the page you requested was not found.</h1>\n<p>Please check the URL for proper spelling and capitalization. If\nyou\'re having trouble locating a destination on Yahoo!, try visiting the\n<strong><a\nhref="http://us.rd.yahoo.com/404/*http://www.yahoo.com">Yahoo! home\npage</a></strong> or look through a list of <strong><a\nhref="http://us.rd.yahoo.com/404/*http://docs.yahoo.com/docs/family/more/">Yahoo!\'s\nonline services</a></strong>. Also, you may find what you\'re looking for\nif you try searching below.</p>\n<form name="s1" action="http://us.rd.yahoo.com/404/*-http://search.yahoo.com/search"><fieldset>\n<legend><label for="s1p">Search the Web</label></legend>\n<input type="text" size=30 name="p" id="s1p" title="enter search terms here">\n<input type="submit" value="Search">\n<span><a href="http://us.rd.yahoo.com/404/*http://search.yahoo.com/search/options?p=">advanced search</a> <span class=sep>|</span> <a href="http://us.rd.yahoo.com/404/*http://buzz.yahoo.com">most popular</a></span>\n</fieldset></form>\n<p class="more">Please try <strong><a\nhref="http://us.rd.yahoo.com/404/*http://help.yahoo.com">Yahoo!\nHelp Central</a></strong> if you need more assistance.</p>\n</div><div id="ft"><p>Copyright &copy; 2012 Yahoo! Inc.\nAll rights reserved. <a\nhref="http://us.rd.yahoo.com/404/*http://privacy.yahoo.com">Privacy\nPolicy</a> - <a\nhref="http://us.rd.yahoo.com/404/*http://docs.yahoo.com/info/terms/">Terms\nof Service</a></p></div>\n</div></body></html>\n'
ipdb> 
```
