and <tt>def_readwrite()</tt>
    member functions provided by <tt>boost::python::class_</tt> for
    direct access to your member data will not work as expected.
    This is because <tt>def_readonly("bar",&nbsp;&amp;foo::bar)</tt> is
    equivalent to:

<pre>.add_property("bar", make_getter(&amp;foo::bar, return_internal_reference()))</pre>

    Similarly, <tt>def_readwrite("bar",&nbsp;&amp;foo::bar)</tt> is
    equivalent to:

<pre>.add_property("bar", make_getter(&amp;foo::bar, return_internal_reference()