给我做一个python 用哈夫曼编码来压缩文字或文件的代码

当然可以。Huffman 编码是一种用于数据压缩的无损压缩算法，它基于构建哈夫曼树的过程。以下是使用 Python 实现哈夫曼编码的一个简单示例，我们将创建一个类来生成和应用编码：

from collections import Counter
import heapq

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

    def __lt__(self, other):
        return self.freq < other.freq

def build_huffman_tree(freqs):
    heap = [Node(char, freq) for char, freq in freqs.items()]
    heapq.heapify(heap)
    
    while len(heap) > 1:
        left = heapq.heappop(heap)
        right = heapq.heappop(heap)
        
        merged = Node(None, left.freq + right.freq)
        merged.left = left
        merged.right = right
        
        heapq.heappush(heap, merged)
    
    return heap[0]

def create_encoding(root):
    encoding = {}
    def traverse(node, code=""):
        if node.char is not None:
            encoding[node.char] = code
        else:
            traverse(node.left, code + "0")
            traverse(node.right, code + "1")
    
    traverse(root)
    return encoding

# 示例文本
text = "hello world"
freqs = Counter(text)

root = build_huffman_tree(freqs)
encoding = create_encoding(root)

compressed_text = "".join(encoding[char] for char in text)
decompressed_text = "".join(encoding[char] for char in compressed_text)

print(f"原始文本: {text}")
print(f"压缩后的文本: {compressed_text}")
print(f"解压后的文本: {decompressed_text}")