title: to_csv() and read_csv() for dataframe containing serialized objects
body: <p>I have proved that the storing and retrieving of a serialized object from the cell of a pandas dataframe is failing after it is stored and loaded again from csv:</p>
  
  <pre><code>a = df['cookie'].iloc[0]
  print (type(a))
  &gt;&gt; &lt;class 'requests.cookies.RequestsCookieJar'&gt;
  </code></pre>
  
  <p>then</p>
  
  <pre><code>df.to_csv('file2.csv')
  df2 = pd.read_csv('file2.csv')
  b = df2['cookie'].iloc[0]
  print(type(b))
  &gt;&gt; &lt;class 'str'&gt;
  </code></pre>
  
  <p>in its cell, it only looks like it differs by a square bracket but</p>
  
  <pre><code>c = '[' + b + ']'
  </code></pre>
  
  <p>..also does not fix it.</p>
  
  <p>By the way: </p>
  
  <pre><code>print(pd.__version__)
  &gt;&gt; '0.19.2'
  </code></pre>
  
  <p>and if you need one of those objects for testing you can make one like this:</p>
  
  <pre><code>import requests
  url = 'http://www.facebook.com/'
  r = requests.get(url)
  c = r.cookies
  </code></pre>
  
  <p>From <a href="https://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.to_csv.html" rel="nofollow noreferrer">pandas.DataFrame.to_csv</a> have tried adding <code>mode='wb'</code> but that only generated an error message.</p>
  
  <p><a href="https://pandas.pydata.org/pandas-docs/stable/generated/pandas.read_csv.html" rel="nofollow noreferrer">pandas.read_csv</a> does not even contain a <code>mode</code> option so if it did work not sure how one would get it back.</p>
  
  <p>Any ideas?</p>