Convert a Sorted Array into a Binary Search Tree(BST) (Leetcode 108)

Problem Link: https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/

class Solution:
    def sortedArrayToBST(self, nums: List[int]) -> Optional[TreeNode]:
                  
        n=len(nums)
        if(n<=0):
            return
        mid=n//2
        data=nums[mid]
        leftchild=self.sortedArrayToBST(nums[:mid])
        rightchild=self.sortedArrayToBST(nums[mid+1:])
        rootnode=TreeNode(data)
        rootnode.left=leftchild
        rootnode.right=rightchild
        return rootnode