Congratulations on implementing the depth-first search algorithm in Python!

To recap this lesson, you gained practice with:

• Using the TreeNode class to store a tree data structure.
• Implementing a recursive method that searches for a path to a node with a specified value using the recursive paradigm often called “divide and conquer.”
• Default function arguments in Python.
• Tuples, which are immutable lists, can be a convenient choice over lists for recursive methods like this.
• Python will implicitly return None from functions that terminate without reaching a return statement, but it can be a good practice to explicitly return None when other components expect None to be returned sometimes.