title: Can't import modules in python: PyQt4 conflicts with SIP
body: <p>I'm new and my english is not very well, but here I go:
  I have the newest Arch Linux on my PC and yesterday I tried to install SIP, a Python code generator for wrapping C++ codes.
  I tried to install SIP and PyQt4 under a virtual enviroment.
  I got SIP from the AUR, and installed it this way:</p>
  
  <p><a href="http://lucacerone.net/2013/08/installing-pyqt4-and-sip-in-a-virtual-environment-ubuntu-1204/#.Uyx-dGd_phF/" rel="nofollow">http://lucacerone.net/2013/08/installing-pyqt4-and-sip-in-a-virtual-environment-ubuntu-1204/#.Uyx-dGd_phF/</a></p>
  
  <p>I did it this way because on the official SIP-documentation website I didn't figure out where to install it and in which directory. The documentation was not clear for me. I know now, that was a very stupid idea because when I try to run a pyhton script with:</p>
  
  <pre><code>python file.py
  </code></pre>
  
  <p>I got errors because I'm using Python 3.3.4:</p>
  
  <pre class="lang-none prettyprint-override"><code>[vain@chinchi2 python_programme]$ python test.py
  Traceback (most recent call last):
    File "test.py", line 25, in &lt;module&gt;
      import matplotlib.pyplot as plt
    File "/usr/lib/python3.3/site-packages/matplotlib/pyplot.py", line 98, in &lt;module&gt;
      _backend_mod, new_figure_manager, draw_if_interactive, _show = pylab_setup()
    File "/usr/lib/python3.3/site-packages/matplotlib/backends/__init__.py", line 28, in pylab_setup
      globals(),locals(),[backend_name],0)
    File "/usr/lib/python3.3/site-packages/matplotlib/backends/backend_qt4agg.py", line 13, in &lt;module&gt;
      from .backend_qt4 import QtCore, QtGui, FigureManagerQT, FigureCanvasQT,\
    File "/usr/lib/python3.3/site-packages/matplotlib/backends/backend_qt4.py", line 21, in &lt;module&gt;
      import matplotlib.backends.qt4_editor.figureoptions as figureoptions
    File "/usr/lib/python3.3/site-packages/matplotlib/backends/qt4_editor/figureoptions.py", line 13, in &lt;module&gt;
      import matplotlib.backends.qt4_editor.formlayout as formlayout
    File "/usr/lib/python3.3/site-packages/matplotlib/backends/qt4_editor/formlayout.py", line 51, in &lt;module&gt;
      from matplotlib.backends.qt4_compat import QtGui,QtCore
    File "/usr/lib/python3.3/site-packages/matplotlib/backends/qt4_compat.py", line 56, in &lt;module&gt;
      from PyQt4 import QtCore, QtGui
  RuntimeError: the sip module implements API v11.0 but the PyQt4.QtCore module requires API v10.1
  </code></pre>
  
  <p>What exactly should I change? I also tried:</p>
  
  <pre><code>sudo pacman -S pyqt5-common 5.2-1 [installed]
  </code></pre>
  
  <p>(Common PyQt files shared between python-pyqt5 and python2-pyqt5) and:</p>
  
  <pre><code>pacman -Sy python-qscintilla-common
  </code></pre>
  
  <p>Maybe there exists a false library dependency, how can I solve this?</p>
  
  <hr>
  
  <p>Oh, 
  I want to install PyQt5 but I got the same problem, the same error after I did:
  <code>
  python configure.py
  make 
  sudo make install
  </code>
  in the </p>
  
  <p><code>full/virtualenv/path/build/SIP/sip-4.15.5/</code>
  I got the same errors again: </p>
  
  <p><code>from PyQt4 import QtCore, QtGui
  RuntimeError: the sip module implements API v11.0 but the PyQt4.QtCore module requires API v10.1
  [vain@chinchi2 python_programme]$ python2 erstenprog.py 
  Traceback (most recent call last):
    File "erstenprog.py", line 26, in &lt;module&gt;
      import matplotlib.pyplot as plt
  ImportError: No module named matplotlib.pyplot</code></p>
  
  <p>I'm so frustraded, because I wrote to arch linux forum in english and german, I got no answer only to deinstalled it.</p>
  
  <p>How I'm supposed to this?
  I just should follow the advice here:
  <a href="http://lucacerone.net/2013/08/installing-pyqt4-and-sip-in-a-virtual-environment-ubuntu-1204/#.Uyx-dGd_phF/" rel="nofollow">http://lucacerone.net/2013/08/installing-pyqt4-and-sip-in-a-virtual-environment-ubuntu-1204/#.Uyx-dGd_phF/</a></p>
  
  <p>Shoul I integrate PyQt5 in the:</p>
  
  <p><code>full/virtualenv/path/build/PyQT5</code></p>
  
  <p>because it already exists in </p>
  
  <p><code>lib/python3.3/site-packages/PyQt5</code>.</p>