<tt>void *</tt> conversion?</h2>
    <font size="-1"><i>Niall Douglas provides these notes:</i></font><p>
    For several reasons Boost.Python does not support <tt>void *</tt> as
    an argument or as a return value. However, it is possible to wrap
    functions with <tt>void *</tt> arguments or return values using
    thin wrappers and the <i>opaque pointer</i> facility. E.g.:
    <pre>// Declare the following in each translation unit
struct void_; // Deliberately do not define
BOOST_PYTHON_OPAQUE_SPECIALI