Iterating Efficiently in Python with itertools
summary
Concrete examples of Python’s itertools are presented: using count, cycle, and repeat for infinite sequences and round‑robin patterns; chain and chain.from_iterable to flatten logs without loading whole files; and zip_longest with fillvalue to avoid losing data. Demonstrates lazy filtering and slicing with compress and islice, generating combinations, permutations, and Cartesian products (for brute‑force password enumerations), and shows a benchmark where 20,160 combinations drop from ~93.7 ms to ~15.1 ms using itertools while avoiding crashes from loading huge ranges into memory.
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chapters (10)
- 0:00Welcome
- 1:25Efficient iteration
- 3:52Iterators and generators
- 8:06What are itertools
- 11:34Iteration tools
- 16:08Combining iterables
- 22:11Cartesian products and permutations
- 26:22Filtering and grouping
- 29:14Efficiency tips
- 31:21Conclusion
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