Have you tried:
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{let children=fetch('content','list', hash( parent_node_id,$item.node_id,class_filter_type, "include", class_filter_array, array(17)))} {section name=disp loop=$:children}//start a new section with name = disp
{$disp.item.node_id} // second item use the name disp
One tip: From version 3.2.4 and above use instead of nrs in the class_filter_array (for example 17) the identifier name of the classes (for example 'myclass')