title: Undefined symbol in libboost
body: <p>I see the following error</p>
  
  <pre><code>ImportError: /usr/local/lib/libboost_python.so.1.57.0: 
  undefined symbol: PyUnicode_AsUTF8String
  </code></pre>
  
  <p>In .so file I see the following symbol undefined</p>
  
  <pre><code>@Ubuntu-1204-precise-64-minimal:/usr/local/lib$ nm libboost_python.so.1.57.0
  | grep PyUnicode_AsUTF8String
               U PyUnicode_AsUTF8String
  </code></pre>
  
  <p>What could be the reason for this symbol to be undefined?</p>
  
  <p>I checked also ldd and all libraries are in standard places.</p>