Python Itertools

Python itertools By Example

Stephen Gruppetta
Stephen Gruppetta 17 Lessons 50m advanced python stdlib
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The narration in this course is an AI-generated clone of Stephen Gruppetta’s voice, used with Stephen’s consent.

Python’s itertools module is one of the hidden gems of the standard library. Knowing the definitions of its functions isn’t enough, though. Its real power lies in composing those functions into fast, memory-efficient, and readable code.

Rather than introducing itertools one function at a time, this video course works through practical examples that encourage you to think iteratively: you’ll shuffle and deal a deck of cards, analyze seventy years of S&P 500 prices, and pick relay teams for a community swim club.

By the end of this video course, you’ll understand that:

  • The functions in itertools operate on iterators and compose into data pipelines that use far less memory than list-based code.
  • batched() is the built-in way to split an iterable into chunks, and it replaces the hand-rolled grouper() recipe for most jobs.
  • combinations(), permutations(), and product() let you brute-force a problem, but they can trigger a combinatorial explosion.
  • count(), repeat(), cycle(), and accumulate() generate infinite sequences and running totals.
  • pairwise(), groupby(), takewhile(), and dropwhile() turn real data analysis tasks into short, readable pipelines.

The examples in this video course run on Python 3.15. You’ll need Python 3.12 or later for batched(), and Python 3.15 for unpacking in comprehensions.

What’s Included:

  • 17 Lessons
  • Video Subtitles and Full Transcripts
  • 2 Downloadable Resources
  • Accompanying Text-Based Tutorial
  • Interactive Quiz to Check Your Progress
  • Q&A With Python Experts: Ask a Question
  • Certificate of Completion

Downloadable Resources:

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Thinking in Iterators

4 Lessons 8m

  1. 1. Python itertools By Example (Overview)01:36
  2. 2. Combining Iterators Into Pipelines02:25
  3. 3. Saving Memory With Lazy Iterators02:28
  4. 4. Splitting Iterables Into Batches02:22

Brute Force and Infinite Iterators

4 Lessons 9m

  1. 1. Making Change With combinations()03:14
  2. 2. Exploring permutations() and product()02:29
  3. 3. Generating Infinite Sequences02:23
  4. 4. Building Running Totals With accumulate()01:45

Dealing a Deck of Cards

2 Lessons 5m

  1. 1. Shuffling and Cutting the Deck03:02
  2. 2. Dealing Hands and Flattening Lists02:22

Analyzing Real Data

5 Lessons 12m

  1. 1. Comparing Neighbors With pairwise()02:54
  2. 2. Finding the Biggest Gain and Loss02:30
  3. 3. Finding the Longest Growth Streak02:09
  4. 4. Grouping Data With groupby()02:00
  5. 5. Building Relay Teams03:05

Reviewing What You've Learned

2 Lessons 13m

  1. 1. Python itertools By Example (Quiz)12:00
  2. 2. Python itertools By Example (Summary)01:28
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About Stephen Gruppetta

Stephen obtained a PhD in physics and worked as a physicist in academia for over a decade before becoming a Python educator. He's constantly looking for simple ways to explain complex things in Python.

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