Construct Binary Tree from Preorder and Inorder Traversal

class Solution:
    def buildTree(
        self, preorder: list[int], inorder: list[int]
    ) -> TreeNode | None:
        if not preorder or not inorder:
            return None
        root = TreeNode(preorder[0])
        mid = inorder.index(preorder[0])
        root.left = self.buildTree(preorder[1 : mid + 1], inorder[:mid])
        root.right = self.buildTree(preorder[mid + 1 :], inorder[mid + 1 :])
        return root