用python 实现二分查找树

好的，下面是用 Python 实现二分查找树的代码：

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

class BST:
    def __init__(self):
        self.root = None

    def insert(self, val):
        new_node = Node(val)
        if self.root is None:
            self.root = new_node
        else:
            current = self.root
            while True:
                if val < current.val:
                    if current.left is None:
                        current.left = new_node
                        break
                    else:
                        current = current.left
                elif val > current.val:
                    if current.right is None:
                        current.right = new_node
                        break
                    else:
                        current = current.right
    
    def search(self, val):
        current = self.root
        while current is not None:
            if current.val == val:
                return True
            elif current.val > val:
                current = current.left
            else:
                current = current.right
        return False

以上是简单的二分查找树的 Python 实现，可以使用 `insert` 方法插入一个新节点，使用 `search` 方法查找指定值的节点是否存在。