&gt;33</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> </span>
<span class="r-out co"><span class="r-pr">#&gt;</span> </span>
<span class="r-out co"><span class="r-pr">#&gt;</span> $predecessors</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> NULL</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> </span>
<span class="r-out co"><span class="r-pr">#&gt;</span> $inbound_edges</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> NULL</span>
<span class="r-out co"