title: PyCharm cannot find the packages in virtualenv
body: <p>I have the latest PyCharm CE and am using it with <code>virtualenv</code>. I have defined the interpreter as the interpreter in the <code>virtualenv</code>. The Project Interpreter window in PyCharm lists all the packages I have installed. I  confirmed this by running <code>pip freeze &gt; requirements.txt</code> and running through the packages manually.</p>
  
  <p>My problem is that PyCharm won't find certain includes in its editor windows, like <code>Flask-Login</code>:</p>
  
  <p>In <code>from flask.ext.login import current_user, login_user, logout_user, login_required</code> the includes <code>current_user, login_user, logout_user, login_required</code> are all marked as unresolved references.</p>
  
  <p>Am I missing something?</p>