AI Pathfinder (Ages 15-18)

Module 4 of 10

Module 04: Python Basics for AI

3 min read590 words
What you'll learn
Run Python in Colab or locally and read basic errors calmly.Use variables, strings, numbers, lists, dicts, `if`/`for`, and functions.Debug off-by-one and type mistakes with traceback habits.Ship a small personal script as portfolio evidence.

Code is executable intent—notes to your future self that a machine actually runs. Python is the friendliest on-ramp to AI and data; you don’t need to be “a math person,” just patient.

Learning Objectives

By the end of this module, you will be able to:

  • Run Python in Colab or locally and read basic errors calmly.
  • Use variables, strings, numbers, lists, dicts, if/for, and functions.
  • Debug off-by-one and type mistakes with traceback habits.
  • Ship a small personal script as portfolio evidence.

1. Why Python?

Readable syntax, huge community, same language as many AI tutorials.

Fun Fact: Python is named after Monty Python, not snakes.

2. Setup

Colab: colab.research.google.com → new notebook → Shift+Enter to run a cell.

Local (optional): python -m venv .venv, activate, pip install jupyter, run notebook.

Try This! In one sentence, what would you like to automate this semester?

3. Variables, Types, Lists, Dicts (Explain Like You’re Texting)

  • Strings hold text; ints whole numbers; floats decimals; bools True/False.
  • Lists are ordered—indexes start at 0 (classic “computers count from zero” moment).
  • Dicts map labels to values—great for one “student card” with keys like "gpa" and "clubs".

Common errors: SyntaxError (quotes/parens), NameError (typo), IndentationError (spacing in loops/functions).

Concept: Read the last line of the red error first—it usually names the problem.

4. Decisions and Loops

if / elif / else choose paths. for repeats over a list or range. while repeats while a condition holds—easy to make infinite loops on purpose or by accident.

Try This! With a friend, trade three-line broken snippets—first fix wins a snack.

5. Functions

A function names a job once: inputs (parameters) → output (return). Docstrings (triple-quoted comments) remind future-you what you promised.

Why it matters: Same spirit as later “tool use” in AI—small, testable pieces.

6. Strings and Tiny Data Stories

strip(), lower(), split(), f-strings like f"Hi {name}" clean messy text. Real projects spend tons of time on boring text cleanup—get cozy early.

7. Debugging Mindset

Errors are messages, not grades. Uncomment one broken line at a time; read the bottom of the traceback aloud; fix; rerun.

Hello, World

Key Example: Your first run + comment style. Everything else in this module extends these two ideas: print output and # comments.

python
[object Object],
,[object Object],(,[object Object],)
,[object Object],(,[object Object],)

Stretch (no new code block): Change the strings to introduce you; add a variable name and an f-string greeting; deliberately break a quote and fix it.

Practice Challenges

input() age + name; list min/max/avg; tiny quiz with dicts in a list; password length checker; three-friend favorite-subject dict.

Your Challenge

Personal utility (50+ lines with comments): study timer, streak counter, club RSVP logger, or deadline list—two functions, one loop, one if branch, one edge case handled.

Discuss: Can a classmate guess what your script does from the first comment block only? If not, clarify the README-style top lines.

Key Takeaways

  • Python is readable and everywhere in AI tutorials.
  • Indices and types cause most early bugs—slow down.
  • Functions organize chaos.
  • Errors are normal—even for pros.

Key Takeaway

  • Treat Python as clear instructions, not magic—computers do exactly what you wrote.
  • Zero-based indexing and types ("3" vs 3) are where beginners trip—check them first.
  • Functions + loops are the skeleton of almost every automation you’ll build later.
  • Read tracebacks from the bottom up; fix one error at a time.
  • Ship one small working program—proof beats intentions.

Going Further

Next: Module 05 (data + plots). Later: Module 08 to save .py / .ipynb as receipts.

You made a machine follow your instructions. That’s not small.