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Table of Contents

Chapter 0: Before You Write Pythonp.3

Chapter 1: Your Three Workspaces — DE, DigiPad, and CLIp.8

this lives in DigiPad as an idea:p.9

Chapter 2: Values, Variables, and Typesp.11

Chapter 3: Input, Output, and Stringsp.16

Chapter 4: Decisions and Program Logicp.21

the comparison operators that make conditions:p.23

Chapter 5: Loops and Repetitionp.26

Chapter 6: Functionsp.32

Chapter 7: Lists, Tuples, and Sequencesp.37

Chapter 8: Dictionaries and Setsp.43

a dict: keys YOU choose -> values you storep.44

Fix 1 — .get() with a default: "answer if you can, otherwise this"p.46

Chapter 9: Strings for Real Programsp.47

Chapter 10: Files, JSON, and Persistencep.51

the SAFE way to open a file: 'with' closes it for you, alwaysp.53

Fix 1 — correct the data: valid JSON has NO trailing commap.54

Fix 2 — defend the program so bad data can't crash itp.55

Chapter 11: Errors, Exceptions, and Debuggingp.56

Option A — guard before you lookp.60

Chapter 12: Modules, Packages, and Virtual Environmentsp.63

greetings.pyp.65

macOS / Linux:p.66

Chapter 13: Object-Oriented Pythonp.70

Chapter 14: Testing and Verificationp.74

Chapter 15: APIs, HTTP, and External Datap.80

Read the secret from the environment — it is NOT in this file.p.84

Chapter 16: Intro to Data with NumPy and Pandasp.85

Chapter 17: Building CLI Applicationsp.91

Chapter 18: Working With AI Without Losing the Skillp.96

Generated by an AI assistant. NOT yet verified. Do not trust — test.p.99

Produced by an AI when asked: "function that takes a monthly budget and ap.103

tasks.py — capstone MVPp.106

Chapter 20: Where Python Goes Nextp.110

Chapter 21: Type Hints & Static Typingp.114

Chapter 22: Decoratorsp.124

Chapter 23: Generators & Iteratorsp.134

Compose them — nothing is read yet; this just wires the pipelinep.137

Chapter 24: Context Managersp.144

Chapter 25: Modern Classesp.154

Chapter 26: Protocols, ABCs & Duck Typingp.164

Chapter 27: Comprehensions & Functional Pythonp.175

map/filter form — note the lambdas and the nestingp.177

comprehension form — the same thing, read left to rightp.178

functional — original untouched, a new list is producedp.179

Chapter 28: Regular Expressionsp.186

search — find the FIRST match anywhere, returns a Match object or Nonep.188

findall — every non-overlapping match, as a list of stringsp.189

Chapter 29: Concurrency I — Threading and the GILp.197

Chapter 30: Concurrency II — Multiprocessing and Parallelismp.207

NO guard — pool starts at module top levelp.211

Chapter 31: Async Python — async/await and asynciop.216

Chapter 32: Packaging and Distributionp.225

pyproject.tomlp.227

Chapter 33: Logging and Configurationp.234

orders.py (a module — a LIBRARY of behavior)p.236

app.py (the APPLICATION — it configures logging, once, at startup)p.237

Chapter 34: Dates, Times, and Time Zonesp.244

stored earlier, by code that used naive local time:p.248

Chapter 35: Performance and Profilingp.253

report.pyp.255

... apply the set() fix ...p.257

Chapter 36: Advanced Testing and Data Persistencep.263

conftest.py — fixtures live here, shared across the test suitep.265

users.pyp.266

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Learn → Think → Write → Run → Observe → Explain → Revise → Save. The first native DigitalExpo DigiPad course.

Operating the three environments. You choose between DigitalExpo, DigiPad and the command line for the job in front of you, and you can say which one settles whether your code is correct. Evidence: you launch Python, run a program, and name the environment that proved it.
Execution as ground truth. You do not claim code works until it has run. Evidence: the interpreter output you point at — not the explanation you gave, and not the one your Coach gave.
Debugging. You read the error, reproduce it in the smallest program that still fails, diagnose before you patch, and verify the repair. Evidence: an unfamiliar broken program, debugged to a fix you can prove.
Testing and verification. You write tests that exercise success, the edges, and failure. Evidence: a test that catches a real defect, including a defect in code an AI wrote.
Working with AI without losing the skill. You read before accepting, diff what changed, test the output, repair what is wrong, and keep architectural authority. Evidence: AI-generated code with subtle bugs — identified, explained, repaired, and verified.

04 · How you'll get there

One loop, on every concept: learn, think, write, run, observe, explain, revise, save. You read in DigitalExpo, you think and write in DigiPad, and you run at the command line, because that is where reality is kept.

Ground truth in this course is execution. Not your Coach's approval, not your reasoning, not an output that looks plausible — the interpreter. Your Coach asks questions, scaffolds, and declines to hand you the answer, because a Coach that writes the program for you has taken the one thing you came for.

Every chapter also breaks something on purpose. That is not a flourish. An error you caused deliberately is the cheapest error you will ever read.

05 · How mastery is judged

Waking your Coach...

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