def add_changes_markup(dom, ins_nodes, del_nodes):
<EOL>for node in reversed(del_nodes):<EOL><INDENT>insert_or_append(node.orig_parent, node, node.orig_next_sibling)<EOL>wrap(node, '<STR_LIT>')<EOL><DEDENT>for node in ins_nodes:<EOL><INDENT>wrap(node, '<STR_LIT>')<EOL><DEDENT>remove_nesting(dom, '<STR_LIT>')<EOL>remove_nesting(dom, '<STR_LIT>')<EOL>sort_del_before_ins(dom)<EOL>merge_adjacent(dom, '<STR_LIT>')<EOL>merge_adjacent(dom, '<STR_LIT>')<EOL>
Add <ins> and <del> tags to the dom to show changes.