
descriptor type, the argument type of <tt>vertex_invariant2</tt> being
<tt>Graph2</tt>'s vertex descriptor type, and both functions having integral
result types.  The values returned by these two functions must be in the range
[0, <tt>vertex_max_invariant</tt>).
<br>
<b>Default:</b> <tt>degree_vertex_invariant</tt> for both arguments<br>
<b>Python</b>: Unsupported parameter.
</blockquote>

IN: <tt>vertex_max_invariant(std::size_t max_invariant)</tt>
<blockquote>
An upper bound on the possible values return