LCA algorithm in a BST

lca_bst.py

# n1.data <= n2.data
def find_lca(tree: BstNode, n1: BstNode, n2: BstNode) -> Optional[BstNode]:
  while tree:
    # both left and right child are greater than current node
    if n1.data > tree.data and n2.data > tree.data:
      tree = tree.right
    
    # both left and right child are less than the current node
    elif n1.data < tree.data and n2.data < tree.data:
      tree = tree.left
    
    # first node that contains n1 and n2 on either child or are equivalent
    else:
      return tree
  return tree