def preorder(t): if t==None: return print t[0], preorder(t[1]) preorder(t[2]) def inorder(t): if t==None: return inorder(t[1]) print t[0], inorder(t[2]) def postorder(t): if t==None: return postorder(t[1]) postorder(t[2]) print t[0], def levelorder(t): q=[t] while q: x=q.pop(0) print x[0], if x[1]: q.append(x[1]) if x[2]: q.append(x[2]) def insert(t, k): if t==None: ..