title: How to downgrade Cython in a virtualenv?
body: <p>How do I downgrade Cython in a virtualenv?</p>
  
  <p>I created it like this:</p>
  
  <pre><code>virtualenv -p python3.4 .
  pip install cython
  </code></pre>
  
  <p>then it installed version <code>Cython-0.22.1.tar.gz</code>.
  However, I am trying to install <code>Kivy</code> in a virtualenv and apparently Cython has a bug that doesn't allow <code>pip install kivy</code> to complete successfully, when that version of Cython is installed. Some people mentioned that you have to downgrade Cython, in order to get Kivy to compile.</p>
  
  <p>So I tried:</p>
  
  <pre><code>pip uninstall cython
  pip install cython 0.20
  </code></pre>
  
  <p>which gives me:</p>
  
  <pre><code>Using cached Cython-0.22.1.tar.gz
  Collecting 0.21.2
  Could not find a version that satisfies the requirement 0.21.2 (from versions: )
  No matching distribution found for 0.21.2
  </code></pre>
  
  <p>So it seems the older version of Cython is somehow not available?</p>
  
  <p>How do I downgrade then?</p>
  
  <p><strong>EDIT#1</strong>:
  Output of <code>pip --version</code>:
      pip 7.1.0</p>