title: Cannot import name StringIO when importing dateutil
body: <p>I'm having a 'Cannot import name StringIO' error message when importing <code>dateutil</code> which tries to import <code>StringIO</code> but cannot find it. Here is complete trace:</p>
  
  <pre><code>(DEV)arbi@el-oued:~/Work/sentimentpy$ python core/main.py
  Traceback (most recent call last):
    File "core/main.py", line 7, in &lt;module&gt;
      from io.reader import *
    File "/home/arbi/Work/sentimentpy/core/io/reader.py", line 4, in &lt;module&gt;
      from dateutil import parser
    File "/home/arbi/DEV/local/lib/python2.7/site-packages/dateutil/parser.py", line 22, in &lt;module&gt;
      from io import StringIO
  ImportError: cannot import name StringIO
  </code></pre>
  
  <p>When I tried to use <code>python3</code>  to launch my program, i had this error:</p>
  
  <pre><code>(DEV)arbi@el-oued:~/Work/sentimentpy$ python3 core/main.py
  Traceback (most recent call last):
    File "core/main.py", line 1, in &lt;module&gt;
      from analyzer.length import LengthAnalyzer
    File "/home/arbi/Work/sentimentpy/core/analyzer/length.py", line 4, in &lt;module&gt;
      from numpy
  ImportError: No module named numpy
  </code></pre>
  
  <p>Why I'm having this? i've installed <code>numpy</code> in my virtualenv with: <code>pip install numpy</code></p>