class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right

class TreeNode:
    def __init__(val=0, left=None, right=None):
        val = val
        left = left
        right = right

class TreeNode:
    def __init__(self, val):
        self.val = val
        self.left = 0
        self.right = 0

def TreeNode(val, left, right):
    return [val, left, right]