@bcipolli see what I'm trying to do here? Imagine if we were trying to insert the content as a child of "/math/"

in ln 186 we append it to the topic node. in 187 we have to reinsert it into the topic tree. we can't just do topic_tree.update -- we have to do something like topic_tree["children"][whatevertheindexofmathis] = parent_node

Does that make sense? Like a robust way of finding how many levels deep we are inserting, and indexing all the way in