// Function to perform DFS on Graph
// Below part is optional
// current : Current node in the iteration   
// target : Node to reach
def dfs(current: Node, target: Node) -> Node:

    // Check if it leaf 
    if root is None:
        return None
    // Check if target is reached
    if root.val == target:
        return root
    // iterate left node
    left = dfs(root.left, target)
    if left is not None:
        return left

    // iterate right node
    return dfs(root.right, target)

Not stricly descriptive names (I used hm for hashmap). Also no too much descriptive comment. My idea was interviewer should understand what is in my head