pan><span class="special">(</span><span class="identifier">PyObject</span><span class="special">*</span> <span class="identifier">callable</span><span class="special">,</span> <span class="identifier">X</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">)</span>
<span class="special">{</span>
   <span class="comment">// Invoke callable, passing a Python object which holds a reference to x</span>
   <span class="identifier">boost</span><span class="special">::</sp