DynamicVibePython learning
How to study · reference & help

One lesson at a time

Read the idea, then follow the named exercise steps. On a phone, use Idea, Code and Output to switch views. Review days begin with recall before the rebuild. A self-review mark is not a scored answer.

Run, inspect, repair

Run loads Python in your browser on the first use, so you need an internet connection. Read Output and the check result. Stop interrupts a run; it keeps your code. Reset restores the selected starter, replacing that exercise’s draft. Use an authored hint before asking for help.

Keep your work

Code drafts, progress and Notes save on this device when browser storage is available. They do not sync through your login. Use Backup & records above to download saved learning records, preview an import or undo the latest import. Copy unsaved text first; clearing browser data can remove local work. A save warning means you should copy your work before leaving.

Practice files and reports

Each browser Run starts in a fresh temporary workspace. A sample file exists only when that run’s code creates it; these are not your computer’s files. On report tasks, use Preview to inspect the actual text and Download to request a copy before another Run, Reset, exercise change or leaving. Reports do not save through tutor login. Read files and write reports.

Get tutoring when you need it

Lessons and checkpoints do not need tutor login. Unlock the tutor through Training’s shared tutor access, then use its return link to come back here. Your question is only sent when you press Send. Do not paste passwords or private production data.

Python words in plain language

Assignment and type
frames = 96 binds a name to an integer. "96" is text, not the same numeric value. Values and names.
List and index
A list keeps items in order. Positions start at zero; the final nonnegative index is length minus one. List lookups.
Loop and indentation
A for loop processes each item. Indentation groups its repeated statements; a statement outside the block runs separately. Loops.
Parameter, argument and Return
A parameter names an input in a definition; an argument supplies its value in a call. Return gives a result to the caller; print displays it. A function that only prints returns None. Functions.
Dictionary and schema
A dictionary labels values with keys. A schema states the required fields and types; a missing fact is not automatically zero. Dictionaries · Validation.
File, CSV and JSONL
A file stores bytes/text. CSV needs a quoting-aware parser; JSONL contains one JSON value per line. Browser practice files are temporary, not computer files. CSV · JSONL.
Denominator and evidence
A rate divides a count by its declared eligible total. Keep exclusions visible. A quiz score, practical check and self-review are different evidence. Quality rates.

Read the error, then make one repair

SyntaxError / IndentationError
Python could not parse the code. Inspect the named line and the preceding line for a missing colon, unmatched quote/bracket or inconsistent indentation. Review blocks.
NameError
A name has no value here. Compare case and spelling, and check that assignment happens before use. Do not replace an unknown parameter with a fixed sample.
TypeError / ValueError
A wrong kind of value or an unacceptable value can fail an operation. Inspect the supplied input and declared policy; do not broadly suppress the error. Narrow error handling.
IndexError / KeyError
The requested position or key is missing. Inspect the collection and interface instead of guessing a fallback. Indices · Keys.
Run stays loading / runtime or checker unavailable
This is not proof that your answer is wrong. Stop if available, copy your draft, check your connection and retry. If it repeats, keep the visible error and use the readable lesson/hints. Never reset or clear browser storage as the first repair.
Expected sample prints, but a check fails
Read the named contract and test changed/empty inputs. The helper may return None, use a fixed value or stop too early even when the sample looks right. A failed check is not a request to copy the expected output.

Press Escape while working inside this panel to close it and return focus to its summary. Without JavaScript, use the summary again. For local Studio commands, use terminal troubleshooting.

← Route Week 5 · Day 21 of 40

JSON records

Loading today's steps…
Lesson idea Tap to fold
Recall

What Python structure stores labelled facts about one item?

Show the answer

A dictionary: each value is reached through a named key.

Today

JSON text is not a Python dictionary

JSON is an interchange format. json.loads reads text into Python values; json.dumps goes the other direction. An object becomes a dictionary, an array becomes a list, true/false become True/False and null becomes None. Valid JSON can also be a number or string, so decoding does not prove you got a record.

JSON property names use double quotes. Malformed text raises json.JSONDecodeError. Printing a dictionary gives Python repr, which is not a JSON export. Spaces and property order do not change the decoded facts; sort_keys=True makes exported property order stable.

# JSON text is not a Python dictionary.
import json

raw = '{"item_id":"Museum","ready":true,"notes":null}'
record = json.loads(raw)
print(record["item_id"])
print(record["ready"], record["notes"])
print(json.dumps(record, sort_keys=True))

Museum, then True None, then JSON with item_id, notes and ready in sorted order. The exported text uses null and true, not Python None and True.

Name the representation before using it: text, decoded data or serialized text. Next, apply the same boundary to one record per line.

Predict, explain, then test

These three brief checks are self-reviewed, not a scored quiz. Answer before opening the comparison. Coding checks follow the stated task assumptions on unfamiliar inputs.

Name the type

What Python values result from JSON true and null?

Compare your answer · self-reviewed

True and None. They are not the strings "true" and "null".

Spot a boundary

Does json.loads("[]") prove a record dictionary was decoded?

Compare your answer · self-reviewed

No. It produces a list; valid JSON syntax alone does not validate a record shape.

Choose serialization

Is str({"ready": True}) a JSON export?

Compare your answer · self-reviewed

No. Python repr can contain single quotes and True; use json.dumps.

Now

Choose an exercise to load its prompt.

day-21.py standard Python · runs in this browser
Output

Loading exercises…


    
    

      
      

        
        
      

    

  














  

    
AI Tutor

    
The tutor mounts here when JavaScript is available. The lesson above stays readable without it.