python代码实现哈夫曼编码

好的，我可以回答这个问题。以下是Python代码实现哈夫曼编码的示例：

from heapq import heappush, heappop, heapify
from collections import defaultdict

def encode(symb2freq):
    heap = [[freq, [symb, ""]] for symb, freq in symb2freq.items()]
    heapify(heap)
    while len(heap) > 1:
        lo = heappop(heap)
        hi = heappop(heap)
        for pair in lo[1:]:
            pair[1] = '0' + pair[1]
        for pair in hi[1:]:
            pair[1] = '1' + pair[1]
        heappush(heap, [lo[0] + hi[0]] + lo[1:] + hi[1:])
    return sorted(heappop(heap)[1:], key=lambda p: (len(p[-1]), p))

# Example usage:
txt = "this is an example for huffman encoding"
symb2freq = defaultdict(int)
for char in txt:
    symb2freq[char] += 1
huff = encode(symb2freq)
print("Symbol\tWeight\tHuffman Code")
for p in huff:
    print("%s\t%s\t%s" % (p[0], symb2freq[p[0]], p[1]))

这个代码使用了默认字典来计算每个字符的频率，然后使用堆来构建哈夫曼树，并编码每个字符。