I'm using Sklearn's KNN to build a classifier and was wondering if there is any way to visualize the decision tree that the algorithm builds. Maybe something of this fashion
$k$-NN does not build a decision tree to classify a new instance, it looks at the class of the most similar examples (the nearest neighbours) in the training set. So, in short, no you cannot get a decision tree from $k$-NN. You can build a decision tree for your dataset directly by using scikit-learn's
DecisionTreeClassifier instead if you need a decision tree.