//Draw the tree here using the graphTree function. It could look simlar to that.
//graphTree(hierarchyData, {label: d => d.data.name})
//Add the depth and height information to the nested data
md` The tree graph needs nested data with specific information of the nodes, this includes height and depth. Have a look at the nest and hierarchy functionalities in D3. Remember to include the functionality to alter the order of the level in the tree according to the order in category_array.`
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