boltons_quickstart_orderedmultidict_lru_cache_iterutils.py

1from boltons.dictutils import OrderedMultiDict
2from boltons.cacheutils import LRU
3from boltons.iterutils import chunked
4
5# 1. OrderedMultiDict: A dictionary that maintains order and allows multiple values per key
6omd = OrderedMultiDict([('a', 1), ('b', 2)])
7omd.add('a', 3)
8print(f"OrderedMultiDict values for 'a': {omd.getlist('a')}")
9# Output: [1, 3]
10
11# 2. LRU Cache: A simple Least Recently Used cache
12cache = LRU(max_size=2)
13cache['a'] = 1
14cache['b'] = 2
15cache['c'] = 3  # This will evict 'a'
16print(f"Cache keys after eviction: {list(cache.keys())}")
17# Output: ['b', 'c']
18
19# 3. Iterutils: Helpful iteration patterns like chunking
20data = [1, 2, 3, 4, 5, 6, 7]
21chunks = chunked(data, 3)
22print(f"Chunked data: {list(chunks)}")
23# Output: [[1, 2, 3], [4, 5, 6], [7]]