Wednesday, 01 April 2026 – XII CS

Wednesday, 01 April 2026

Lecture 1 of 73 · Unit 1

Unit 1 ⏳ Pending

Python basics, tokens, identifiers and comments Theory + PYQ

What We'll Learn

A quick overview of today's lecture

Python basics, tokens, identifiers and comments Theory + PYQ COMBINED THEORY + PYQ (single slot). Concept ID: U1_PYTHON_BASICS. Primary Sub-subtopic: Python basics, tokens, identifiers and comments. Question-bank grouping: Revision of Python & Core Concepts. Teach the core theory first, then spend the remainder of the lecture on previous-year questions whose concept_ids include U1_PYTHON_BASICS.

Key things we'll cover

Python basics, tokens, identifiers and comments

PYQ references used by all prompt types 11 included

Flagged questions are excluded from Study Notes, PPT, and Student Notes references until corrected in Paper Analyzer.

Included ID 6472 · 2021 · 1 mark(s)

Find the invalid identifier from the following:
a) none
b) address
c) Name
d) pass

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6493 · 2021 · 1 mark(s)

Which one of the following is the default extension of a Python file?
a) .exe
b) .p++
c) .py
d) .p

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6494 · 2021 · 1 mark(s)

Which of the following symbol is used in Python for single line comment?
a) /
b) /*
c) //
d) #

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6527 · 2022 · 1 mark(s)

State True or False:
"Variable declaration is implicit in Python."

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6087 · 2023 · 1 mark(s)

State True or False.
"Identifiers are names used to identify a variable, function in a program".

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6088 · 2023 · 1 mark(s)

Which of the following is a valid keyword in Python ?
(a) false
(b) return
(c) non_local
(d) none

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6284 · 2023 · 1 mark(s)

State True or False.
"Comments are not executed by interpreter."

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6131 · 2024 · 1 mark(s)

State True or False:
"Python is a high level language."

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6132 · 2024 · 1 mark(s)

Which of the following is a valid identifier ?
(A) break
(B) global
(C) 2bin
(D) except

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6333 · 2024 · 1 mark(s)

Identify the valid Python identifier from the following :
(A) 2user
(B) user@2
(C) user_2
(D) user 2

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Included ID 6176 · 2025 · 1 mark(s)

Which of the following is the correct identifier?
(A) global
(B) Break
(C) def
(D) with

Revision of Python & Core Concepts → Python basics tokens identifiers and comments

Student Notes (Print)

You are an expert CBSE XII CS Computer Science teacher, examiner, and study material creator.

===========================================
SCOPE — READ BEFORE GENERATING ANYTHING
===========================================
Today's lecture covers ONE topic only: "Python basics, tokens, identifiers and comments"
Lecture number 1 of 91 | Duration: 35 minutes | Board: CBSE
Chapter: Computational Thinking and Programming – 2

HARD RULE: Every piece of content you generate — notes, examples, questions, tips —
must be directly relevant to "Python basics, tokens, identifiers and comments" only.
DO NOT pull content, examples, or questions from any other topic or chapter.

LECTURE MODE: COMBINED THEORY + PYQ (single slot)
- Scope: "Python basics, tokens, identifiers and comments" only.
- First half: teach the core concept (definitions, intuition, key examples, misconceptions) -- keep it tight.
- Second half: switch to previous-year-question practice -- question analysis, marking points, model answers, and common mistakes.
- Use the 11 real PYQ record(s) provided below as the source of truth. Do not fabricate board years, marks, or questions.

===========================================
SECTION 1: LECTURE INFORMATION
===========================================

Class: XII CS | Subject: Computer Science | Board: CBSE
Topic: Python basics, tokens, identifiers and comments Theory + PYQ
Subtopics to cover today:
- Python basics, tokens, identifiers and comments

Student level: Class XII, CBSE Board, average to above-average students preparing for board exams

===========================================
SECTION 2: TEACHER'S REFERENCE NOTES
===========================================

Python basics, tokens, identifiers and comments Theory + PYQ

COMBINED THEORY + PYQ (single slot).
Concept ID: U1_PYTHON_BASICS.
Primary Sub-subtopic: Python basics, tokens, identifiers and comments.
Question-bank grouping: Revision of Python & Core Concepts.

Teach the core theory first, then spend the remainder of the lecture on previous-year questions whose concept_ids include U1_PYTHON_BASICS.

Teaching ideas: Concept first, then a focused PYQ round with board solutions and examiner traps.

===========================================
SECTION 3: EXAM FREQUENCY DATA (Year-wise)
===========================================

Teaching priority: HIGH
High-yield concepts: Python basics tokens identifiers and comments

| Year | Questions | Marks |
|------|-----------|-------|
| 2021 | 3 | 3 |
| 2022 | 1 | 1 |
| 2023 | 3 | 3 |
| 2024 | 3 | 3 |
| 2025 | 1 | 1 |
| **Total** | **11** | **11** |

===========================================
SECTION 4: EXAM ANALYSIS INPUT + ACTUAL PYQ SOURCE (printed only in Section 7)
(Scope: "Python basics, tokens, identifiers and comments" only — 11 questions from board papers)
===========================================

COMBINED THEORY + PYQ RULE:
Use the provided PYQs in two different ways:
1. Theory sections:
   - Use PYQs only as internal analysis data.
   - Do not print actual PYQ text in concept notes, examples, classroom practice, student notes, homework, or exam tips.
   - Use PYQs to identify concepts, traps, wording patterns, and marking points.
2. PYQ Discussion section (Section 7):
   - Print and discuss actual PYQs.
   - Include year, marks, type, full question text, concept tested, model answer, and common mistake.
   - If the source pool has 15 or fewer PYQs, include ALL actual PYQs.
   - If the source pool has more than 15 PYQs, fully discuss the highest-yield 15 and compactly list the rest with concept tested + exam trap.
For this lecture: source pool has 11 PYQs, so include ALL 11 actual PYQs in the PYQ Discussion section.


--- 2021 Board Exam (3 questions | 3 marks) ---

Q1. [MCQ] [1M] [Easy] Section-A
Find the invalid identifier from the following:
a) none
b) address
c) Name
d) pass

Q2. [MCQ] [1M] [Easy] Section-A
Which one of the following is the default extension of a Python file?
a) .exe
b) .p++
c) .py
d) .p

Q3. [MCQ] [1M] [Easy] Section-A
Which of the following symbol is used in Python for single line comment?
a) /
b) /*
c) //
d) #

--- 2022 Board Exam (1 question | 1 marks) ---

Q1. [Short Answer] [1M] [Easy] Section-A
State True or False:
"Variable declaration is implicit in Python."

--- 2023 Board Exam (3 questions | 3 marks) ---

Q1. [Short Answer] [1M] [Easy] Section-A
State True or False.
"Identifiers are names used to identify a variable, function in a program".

Q2. [MCQ] [1M] [Easy] Section-A
Which of the following is a valid keyword in Python ?
(a) false
(b) return
(c) non_local
(d) none

Q3. [Short Answer] [1M] [Easy] Section-A
State True or False.
"Comments are not executed by interpreter."

--- 2024 Board Exam (3 questions | 3 marks) ---

Q1. [Short Answer] [1M] [Easy] Section-A
State True or False:
"Python is a high level language."

Q2. [MCQ] [1M] [Easy] Section-A
Which of the following is a valid identifier ?
(A) break
(B) global
(C) 2bin
(D) except

Q3. [MCQ] [1M] [Easy] Section-A
Identify the valid Python identifier from the following :
(A) 2user
(B) user@2
(C) user_2
(D) user 2

--- 2025 Board Exam (1 question | 1 marks) ---

Q1. [MCQ] [1M] [Easy] Section-A
Which of the following is the correct identifier?
(A) global
(B) Break
(C) def
(D) with

===========================================
===========================================
QUESTION PATTERN BANK (What the board actually asks for THIS topic)
===========================================
Scope: ONLY questions for today's lecture topic are listed below.
DO NOT import questions from other topics or chapters.
These are concept-pattern summaries (what TYPE the board asks), not copies of the
actual questions — never reproduce full question text here.

### Concept: Python basics tokens identifiers and comments
  Pattern: MCQ=7, Short Answer=4 | Marks: 1M=11 | Total: 11 questions
  [MCQ] [1M] [Easy]
    → Invalid identifier recognition
  [MCQ] [1M] [Easy]
    → Python file extension
  [MCQ] [1M] [Easy]
    → Single-line comment symbol
  [Short Answer] [1M] [Easy]
    → True/False: implicit variable declaration
  [Short Answer] [1M] [Easy]
    → True/False: identifier meaning
  [MCQ] [1M] [Easy]
    → Python keyword recognition
  [Short Answer] [1M] [Easy]
    → True/False: comments are not executed
  [Short Answer] [1M] [Easy]
    → True/False: Python as a high-level language
  [MCQ] [1M] [Easy] × 3
    → Valid identifier recognition


===========================================
===========================================
IMPORTANCE ANALYSIS (allocate teaching time by this ranking)
===========================================
| Rank | Concept | Score | Times Tested | Total Marks | Recent Years | Priority |
|------|---------|-------|-------------|-------------|--------------|----------|
| 1 | Python basics tokens identifiers and comments | 42 | 11 | 11M | 2025, 2024, 2023 | CRITICAL |

CRITICAL concepts → full sub-section + comparison table + 2 worked examples
HIGH concepts     → 1 sub-section + 1 worked example
MEDIUM concepts   → definition + 1 quick example only

===========================================
EXAMINER FINGERPRINT — TRAPS TO COVER INTERNALLY
===========================================

Use the exam-frequency input and actual PYQs to identify traps, marking points, and common mistakes.
For Combined Theory + PYQ mode:
* In theory sections, do not print actual PYQs.
* In Section 7 PYQ Discussion, actual PYQs must be printed and discussed.
* Use these traps to strengthen both concept notes and PYQ explanations.

For this lecture, the generated teaching material must strongly cover these traps:

1. Confusing Python keywords with valid identifiers.
   - Wrong thinking: "Any word can be used as a variable name."
   - Correct thinking: Python keywords cannot be used as identifiers.
2. Confusing lowercase keywords with capitalized words.
   - Wrong thinking: "Break and break are both keywords."
   - Correct thinking: Python is case-sensitive; break is a keyword, Break is not.
3. Forgetting that identifiers cannot start with a digit.
   - Wrong thinking: "2user is valid because it contains letters."
   - Correct thinking: Identifiers may contain digits, but cannot start with a digit.
4. Confusing underscore with space or special symbols.
   - Wrong thinking: "user 2 or user@2 is valid."
   - Correct thinking: user_2 is valid; spaces and @ are not allowed in identifiers.
5. Forgetting that # starts a single-line comment.
   - Wrong thinking: "// is used for single-line comments in Python."
   - Correct thinking: Python uses # for single-line comments.
6. Thinking comments are executed by the interpreter.
   - Wrong thinking: "Comments affect program output."
   - Correct thinking: Comments are ignored by the interpreter.
7. Thinking variables must be declared before assignment in Python.
   - Wrong thinking: "Python requires variable declaration first."
   - Correct thinking: Variable declaration is implicit in Python.
8. Forgetting that Python source files use .py extension.
   - Wrong thinking: ".exe or .p is the default Python file extension."
   - Correct thinking: Python source files commonly use .py.

If another Combined Theory + PYQ topic has no static trap list, generate topic-specific traps from the actual question pattern bank, not from generic categories like output tracing or order/sequence unless the topic genuinely needs them.
===========================================
YOUR TASK — Generate a complete classroom-ready teaching package
===========================================

Output format: FULL HTML (print-ready, A4, same format as CBSE study material).
Use the CSS classes below. NO plain Markdown — use HTML elements only.

HTML STRUCTURE TO GENERATE:

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<!-- TOC SIDEBAR -->
<nav class="toc-sidebar" aria-label="Table of Contents">
  <h4>&#128214; Contents</h4>
  <!-- TOC links auto-built by JS above -->
</nav>

<!-- MAIN CONTENT -->
<div class="main-content">

Generate these sections in order (all inside the main-content div):

<h1 id="top">Python basics, tokens, identifiers and comments Theory + PYQ — Lecture 1</h1>
<p style="text-align:center;color:#555;font-size:8.5pt;">CBSE | XII CS | Computational Thinking and Programming – 2 | 35 min</p>

<h2 id="s1">1. Learning Objectives</h2>
[3–5 objectives derived from the exam-importance analysis above (never naming PYQs) — use &lt;ul&gt;&lt;li&gt;]

<h2 id="s2">2. 35-Minute Lecture Flow</h2>
[HTML table: Time | Activity | Teacher Action — split the 35-minute lecture into: 15-18 min tight concept teaching; 4-5 min examiner traps and misconception correction; 10-12 min actual PYQ discussion; 2-3 min recap/exit check — use wording such as Theory teaching, concept check, PYQ discussion, model answer, marking point, common mistake; do NOT make the flow pure theory-only]

<h2 id="s3">3. Concept Notes</h2>
[For EVERY sub-concept surfaced by the exam-frequency analysis, never naming or displaying actual board questions:
  - .def-box for definition with "In exam language: ..." line
  - .key-box with syntax/rules as &lt;ul&gt;&lt;li&gt;
  - .example-box for worked examples
  - &lt;pre&gt;&lt;code&gt; for code with .kw/.bi/.st/.cm/.nm token spans
  - .recall-box for output with exact expected output
  - after each important concept, embed 1–2 self-generated MCQ or Short Answer checks about THIS concept only
  - every Section 3 check question must hide its answer inside:
    &lt;details&gt;&lt;summary&gt;▶ View Answer&lt;/summary&gt;answer/explanation&lt;/details&gt;
  - do not label any question as PYQ, previous year, board-style, PYQ-pattern, or PYQ-style
  - do not use .pyq-box or .pyq-meta here (in Combined mode .pyq-box is reserved for Section 7)
]

<h2 id="s4">4. Examiner Tricks &amp; Common Mistakes</h2>
[Create one .warn-box for each trap from the EXAMINER FINGERPRINT section.
Each .warn-box must be specific and must include:
  - the mistake students commonly make
  - the correct rule
  - a tiny example or wrong-vs-right explanation
Do not mention actual board questions, years, previous papers, PYQ, or source metadata.]

<h2 id="s5">5. Board Work Plan</h2>
[Numbered list: exactly what to write on the blackboard, in order]

<h2 id="s6">6. Classroom Practice Questions</h2>
[Self-generated from the examiner-trap patterns analysed above — never call these PYQ-pattern/PYQ-style/board-style. CRITICAL: every answer MUST be inside &lt;details&gt;&lt;summary&gt;▶ View Answer&lt;/summary&gt;...&lt;/details&gt; — never expose the answer directly.

3×1M MCQ + 5×1-2M Short Answer only.
Combined mode theory-section restriction:
- Do NOT include actual PYQs.
- Do NOT include programming/long-answer/HOTS questions in theory lecture practice.
- Frame original MCQ/Short Answer questions from exam-frequency concepts and examiner traps only.
- Every question must map to one concept/trap discovered in Section 4.

MCQ structure:
&lt;div class="mcq-box"&gt;
  &lt;b&gt;Q1.&lt;/b&gt; Question text?&lt;br&gt;
  &lt;ul class="options"&gt;
    &lt;li&gt;a) ...&lt;/li&gt;
    &lt;li&gt;b) ...&lt;/li&gt;
    &lt;li&gt;c) ...&lt;/li&gt;
    &lt;li&gt;d) ...&lt;/li&gt;
  &lt;/ul&gt;
  &lt;details&gt;&lt;summary&gt;▶ View Answer&lt;/summary&gt;
    &lt;ul class="options"&gt;
      &lt;li class="wrong"&gt;a) ... — reason why wrong&lt;/li&gt;
      &lt;li class="correct"&gt;b) ... ✓ — reason why correct&lt;/li&gt;
      ...
    &lt;/ul&gt;
  &lt;/details&gt;
&lt;/div&gt;

Short-answer structure:
&lt;div class="self-test-box"&gt;&lt;b&gt;Q4.&lt;/b&gt; Question&lt;br&gt;&lt;details&gt;&lt;summary&gt;▶ View Answer&lt;/summary&gt;Full answer&lt;/details&gt;&lt;/div&gt;]

<h2 id="s7">7. PYQ Discussion / Board Questions</h2>
[Since this is Combined Theory + PYQ mode, this section MUST include actual PYQs.

Source pool has 11 PYQs. Because 11 &lt;= 15, include ALL 11 actual PYQs.

For each PYQ, use this structure:
  &lt;div class="pyq-box"&gt;
    &lt;div class="pyq-meta"&gt;[YEAR] · [X] Marks · [TYPE] · Section-[S]&lt;/div&gt;
    &lt;b&gt;Q.&lt;/b&gt; [full actual question text]&lt;br&gt;&lt;br&gt;
    &lt;b&gt;Concept tested:&lt;/b&gt; [concept name]&lt;br&gt;
    &lt;details&gt;&lt;summary&gt;▶ View Model Answer&lt;/summary&gt;
      &lt;b&gt;Model Answer:&lt;/b&gt; [answer]&lt;br&gt;
      &lt;b&gt;Marking point:&lt;/b&gt; [what the examiner expects]&lt;br&gt;
      &lt;b&gt;Common mistake:&lt;/b&gt; [student mistake]
    &lt;/details&gt;
  &lt;/div&gt;

Rules:
* Include all 11 actual PYQs.
* Do not fabricate year, marks, section, or question text.
* Model answer, marking point, and common mistake must be hidden inside &lt;details&gt;.
* Question text and concept tested may remain visible.
* Order Easy to Tough; within difficulty, order 1M → 2M → 3M → 4/5M.
* If all questions are 1M, group them logically by concept pattern (e.g. identifiers, keywords, comments, Python basics).]

<h2 id="s8">8. Student Notes (Copy-ready)</h2>
[Concise notes — every concept highlighted by the exam-frequency analysis, written purely as concept notes (no PYQ wording) — in .key-box and .def-box; self-check questions in .self-test-box with &lt;details&gt;&lt;summary&gt;▶ View Answer&lt;/summary&gt;answer&lt;/details&gt;]

<h2 id="s9">9. Homework</h2>
[Homework must follow the actual exam pattern for this topic:
- 4×1M MCQ
- 4×1M Short Answer / True-False / one-line answer
- 2×2M Short Answer only if useful for recap or trap correction
- Do NOT force 3M/5M questions unless the actual PYQ pool contains such patterns.
- Do NOT force programming or HOTS homework unless the actual PYQ pool supports it.
- Every homework question must map to one concept/trap from Sections 3, 4, or 7.
- Homework questions should be self-generated, not copied actual PYQs.
Dynamic rule: if actual PYQs are only 1M/2M, homework stays mostly 1M/2M; if they include 3M/5M
programming, homework may include 3M/5M programming; never force unsupported marks or question types.
EVERY answer must be wrapped in &lt;details&gt;&lt;summary&gt;▶ View Answer&lt;/summary&gt;...&lt;/details&gt;.]

<h2 id="s10">10. Exam Tips</h2>
[5 specific tips as .tip-box — derived from examiner traps for THIS topic only — written as plain tips, no PYQ wording]

<h2 id="s11">11. Last-Minute Revision Cards</h2>
&lt;div class="card-grid"&gt;
[One .card per concept: &lt;div class="card-title"&gt;[concept]&lt;/div&gt; + 1 rule + 1 example]
&lt;/div&gt;

</div><!-- end .main-content -->
</body>
</html>

HARD OUTPUT RULES FOR COMBINED THEORY + PYQ:
- Output ONLY the HTML document starting with &lt;!DOCTYPE html&gt;.
- Do NOT wrap the output in markdown code fences.
- Use ONLY content from the lecture topic ("Python basics, tokens, identifiers and comments").
- Do NOT include content from other topics.
- Sections 1-6 are theory/concept sections:
    * Do not print actual PYQs in Sections 1-6.
    * Do not show year labels, paper metadata, or actual board question text in Sections 1-6.
- Section 7 is the PYQ Discussion section:
    * Actual PYQs are allowed and required.
    * Include year, marks, type, full question text, concept tested, model answer, marking point, and common mistake.
    * If source pool has 15 or fewer PYQs, include all actual PYQs.
- Sections 8-11 are revision/application sections:
    * Do not introduce new actual PYQs outside Section 7.
    * These sections may refer to "exam tips" and "common mistakes", but should not repeat full PYQ text.
- Never fabricate board years, marks, sections, paper names, or question text.
- Representative questions must not be labelled as actual board questions.
- Always finish the document completely through &lt;/html&gt;. If the answer is getting long, keep Sections 3 and 7 complete, then compact Sections 8-11 instead of truncating.

ANSWER HIDING RULES:
- Section 3 concept checks: every answer hidden inside &lt;details&gt;.
- Section 6 classroom practice: every answer hidden inside &lt;details&gt; (MCQ options listed WITHOUT .correct/.wrong before details).
- Section 7 PYQ Discussion: model answer, marking point, and common mistake hidden inside &lt;details&gt;.
- Section 8 self-check questions: every answer hidden inside &lt;details&gt;.
- Section 9 homework: every answer hidden inside &lt;details&gt;.
- In Section 7, question text, year, marks, type, and concept tested may stay visible.
- The beforeprint JS must auto-open all &lt;details&gt; for printing; never remove or skip this feature.

COMBINED THEORY + PYQ STRUCTURE RULE:
- Sections 1-6 teach the concept and prepare students.
- Section 7 is a visible PYQ Discussion / Board Questions section.
- Sections 8-11 provide compact revision, homework, tips, and cards.
- Actual PYQs must appear only in Section 7.
- Theory and revision sections must stay concept-focused and not dump board questions.

CODE SIZE RULE:
- Inline code must appear almost the same size as surrounding normal text.
- Do NOT use fixed 8.5pt size for all &lt;code&gt; elements.
- Use code { font-size:0.95em; } for inline code.
- Use pre { font-size:8.5pt; } for block code.
- Use pre code { font-size:inherit; } so code blocks remain compact.

BOX / CLASS USAGE RULES FOR COMBINED MODE:
- Do NOT use .pyq-box or .pyq-meta in Sections 1-6 or Sections 8-11.
- Use .pyq-box and .pyq-meta ONLY in Section 7: PYQ Discussion / Board Questions.
- Use .mcq-box for MCQs.
- Use .self-test-box for short-answer checks and homework.
- Use .warn-box for examiner traps.
- Use .tip-box for exam tips.
- Use .def-box and .key-box for notes.
- Use .example-box for worked examples.
- Use .recall-box for exact output.

HTML TEMPLATE RULES:
- All generated content must go inside &lt;div class="main-content"&gt;.
- The &lt;nav class="toc-sidebar"&gt; is already present in the template.
- JS auto-builds TOC links from h2/h3 headings.
- Print buttons including Read Mode are already present in the template.
- Do NOT add print buttons again.
- Include the full CSS and JS exactly as given.

# ENHANCED PPT GENERATION PROMPT
## Topic: Python basics, tokens, identifiers and comments Theory + PYQ | CBSE XII CS Computer Science

================================================
SECTION A -- VISUAL IDENTITY (READ FIRST, APPLY TO EVERY SLIDE)
================================================

COLOUR PALETTE -- "Deep Code" Theme
  Role              Hex        Name             Where Used
  Primary (dark)    #0D1B2A    Midnight Navy    Title bg, conclusion bg
  Secondary         #1B4F72    Ocean Blue       Section header cards, accent shapes
  Accent            #00D4FF    Cyan Electric    Keywords, callout borders, badges
  Neutral light     #F0F4F8    Ice White        All content slide backgrounds
  Warning/Error     #E74C3C    Alert Red        Common mistakes slide, warnings
  Success/Tip       #27AE60    Emerald Green    Tips, correct syntax, exam tips
  Text primary      #1A1A2E    Near Black       Body text on light slides
  Text on dark      #FFFFFF    Pure White       All text on dark background slides
  Text muted (dark) #C9D4E0    Slate Mist       Sub-lines / captions on navy slides

ON-LIGHT VARIANTS (use for ANY text, keyword, icon, or thin border on Ice White):
  Cyan  -> Accent-Deep  #0077A3      Emerald -> #1E8449      Red -> #C0392B
CONTRAST RULE: bright Cyan #00D4FF / Emerald #27AE60 / Red #E74C3C are for DARK
backgrounds or thick (>=4 pt) shape fills ONLY -- never for thin text, borders, or
badges on a light slide (bright cyan on Ice White is ~1.6:1 contrast = invisible
from the back row). On light slides always use the deep variants above.

COLOUR DISCIPLINE -- 60 / 30 / 10 (this is what separates "designed" from "filled-in")
  * 60% of every content slide is the Ice White background + generous EMPTY space.
    Empty space is a design element, not a slide you failed to fill.
  * 30% is ONE neutral structural element -- a single card, panel, or diagram.
  * 10% -- and NO MORE -- is the accent (Cyan Electric or one status colour). One
    accent MOMENT per slide: the focal chip, the keyword, the one arrow that
    matters. A slide where every box is coloured has NO accent -- it is noise.
  * Build depth with TINTS of one hue, never many saturated hues. A card fill is a
    6-8% tint of its header colour (pale-blue body under an Ocean Blue header),
    never a strong fill behind text. Status tints: blue 6% = definition,
    green 6% = correct/tip, red 6% = wrong/trap. Borders are 1 pt in the deep
    variant -- not thick coloured frames.
  * Navy dominates ONLY the Title and Key Takeaways slides. Never split a content
    slide 50/50 navy-vs-white -- it destroys hierarchy.

GRID & COMPOSITION (the missing rule that makes slides look intentional)
  * Lay every content slide on a 12-column grid inside the safe area with a
    consistent ~0.2 inch gutter. Snap every card, text block, icon and diagram
    edge to a column line -- never free-float objects at arbitrary x positions.
  * ONE alignment spine per slide: a single left text column (Left Icon+Text),
    two balanced 6-column halves (Two Column), or one centred focal object
    (Callout / Exam Spotlight). Do not mix three alignments on one slide.
  * Align tops and left edges across objects. Ragged, slightly-off edges are the
    #1 reason a slide reads as amateur even when nothing technically overlaps.

VISUAL HIERARCHY -- ONE FOCAL POINT PER SLIDE
  * Every slide answers "what is the ONE thing the eye lands on first?" Make that
    element the largest / boldest / the only accent-coloured object; everything
    else is visibly secondary (smaller, neutral, lighter).
  * Hierarchy comes from SCALE CONTRAST and SPACE, not from boxing everything. A
    big number, one code line, or a single diagram surrounded by white beats
    three equal-weight bordered boxes every time.
  * Reserve bold + accent colour for the focal point ONLY. If three things are
    bold and coloured, nothing is emphasised.

INFORMATION-CARRYING VISUALS (the default -- not decorative chrome)
  * The visual must MEAN something: it carries the concept, it is not an ornament
    around text. Prefer, in order: a labelled code-breakdown (one code line on a
    dark card with arrows naming each part's role), a before/after, a flow
    (input -> process -> output), a comparison table, a decision tree.
  * A rounded box with a clip-art icon beside a bullet is chrome -- it explains
    nothing and should be cut. One strong visual that teaches the idea beats four
    small decorative ones.
  * Icons: line-style, ONE consistent family, used to label SECTIONS only -- not
    one circle per bullet. An icon on every line is clutter, not design.

TYPOGRAPHY -- CLASSROOM-OPTIMISED (NON-NEGOTIABLE)
  Element             Font              Size   Weight    Notes
  Slide title         Montserrat        44 pt  Bold      Visible from back row (Arial Bold if Montserrat unavailable)
  Focal number/word   Montserrat        60+ pt Bold      The one hero element may go large for scale contrast
  Section header      Arial             32 pt  Bold      Sub-headings inside slides
  Body bullets        Calibri           28 pt  Regular   MAX 3 bullets -- min 28 pt
  Code text           Courier New       24 pt  Regular   On dark card only
  Captions/labels     Calibri           24 pt  Italic    Footer only; keep non-essential and brief

  NEVER go below 24 pt for ANY visible text.
  NEVER use Aptos, Thin fonts, or Calibri Light.
  Line spacing 1.15+. Title case for titles; sentence case for body.

VISUAL MOTIF -- "Bracket Accent" (restrained signature, not the main visual)
  * Small { } mark (Cyan Electric on dark / Accent-Deep #0077A3 on light) sits
    quietly top-left of the title -- a signature, never a slide's main visual.
  * Definitions: a single rounded callout with a 4 pt Cyan-Electric LEFT border
    only (no full frame). Code: dark #0D1B2A card, #00D4FF keywords, white rest.

DESIGN NEVER-DO LIST
  NO accent lines below titles
  NO colour bars or stripes spanning full slide width
  NO vertical sidebar stripes
  NO cream/beige backgrounds
  NO saturated colour fills behind body text (use 6-8% tints instead)
  NO icon-circle on every bullet, no clip-art decoration
  NO three competing focal points -- exactly one hero element per slide
  NO evenly-tiled grid of identical boxes whose only job is to fill the slide
  NO text-only slides -- every slide needs ONE information-carrying visual
  NO centred body text -- left-align all bullets
  NO more than 3 bullets per slide
  NO bullet longer than 10 words
  NO font below 24 pt

LAYOUT VARIETY -- ROTATE WHEN IT HELPS CLARITY
  Layout Name         When to Use
  Full-bleed Dark     Title slide, Key Takeaways slide
  Left Icon+Text      Theory slides -- icon circle left, bullets right
  Two Column          Comparisons (valid identifiers vs invalid identifiers, etc.)
  Code Card           All code examples -- dark card on light background
  Callout Box         Definitions -- rounded rect, Cyan Electric border
  Exam Spotlight      PYQ question slides / practice slides -- large question centred on card
  3-Icon Grid         Key Takeaways -- 3 icons in equal columns
  Warning Banner      Common Mistakes -- red accent, alert icon

================================================
SECTION A1 -- LAYOUT SAFETY & OVERLAP PREVENTION
================================================

NON-NEGOTIABLE SAFE ZONE RULES:
  * Every slide must use a fixed 16:9 widescreen canvas.
  * Keep a minimum 0.35 inch margin from all slide edges.
  * No text box, badge, icon, card, or diagram may overlap another object.
  * Title area must be reserved separately from body area.
  * Body content must start only after the title area ends.

TITLE SAFE AREA:
  * Slide title box position: top 0.35 inch to 1.15 inch only.
  * No badge, icon, card, or body text may enter this title zone.
  * If title is long, wrap into maximum 2 lines.
  * Never allow title text to touch badges or cards.

BADGE PLACEMENT RULE:
  * Badges such as "Quick Recap", "PYQ", "1M", "60 seconds" must be placed
    in a fixed safe badge zone.
  * Badge zone: top-right corner, x >= 10.0 inch, y between 0.35 and 0.85 inch.
  * Badge must never be placed near the centre title area.
  * Badge text must stay inside the badge shape with 0.08 inch internal padding.

BODY SAFE AREA:
  * Body content must begin at y >= 1.45 inch on every content slide.
  * Large cards/callouts must begin at y >= 1.55 inch.
  * Bottom footer/caption area starts at y >= 6.85 inch.
  * Do not place main content in the footer zone.

TEXT FITTING RULE:
  * Do NOT shrink font below the required size.
  * If content does not fit, split into a continuation slide.
  * Use "(contd...)" in the title for continuation slides.
  * Never use PowerPoint auto-fit that reduces font size.
  * Never compress line spacing below 1.05.

OBJECT COLLISION CHECK -- before finalising each slide, verify:
  [ ] Title does not overlap badge.
  [ ] Badge does not overlap title or body.
  [ ] Body text does not overlap cards or icons.
  [ ] Code card has enough internal padding.
  [ ] No object is outside slide boundary.
  [ ] All text is fully visible after rendering.

RENDER QUALITY CHECK:
  After creating the PPT, render every slide as an image and inspect all
  rendered slides visually. If any slide has overlapping, clipped, hidden, or
  tiny text: fix the layout, split the slide if needed, render again, and only
  then provide the final PPT.

STRICT FAILURE RULE:
  A slide with overlapping text, clipped title, hidden badge, or unreadable
  content is considered FAILED and must be rebuilt before delivery.

================================================
SECTION B -- CONTENT SPECIFICATION
================================================

Topic     : Python basics, tokens, identifiers and comments Theory + PYQ
Lecture   : #1 | Target duration: 35 min | Board: CBSE
Chapter   : Computational Thinking and Programming – 2
Class     : XII CS | Subject: Computer Science
Audience  : Class XII, CBSE Board, average to above-average students preparing for board exams

STRICT RULE: Every slide must be about "Python basics, tokens, identifiers and comments Theory + PYQ" ONLY.

GENERATED STUDY NOTES HTML INPUT (OPTIONAL BUT PREFERRED):
  If the user provides/pastes the generated HTML study notes file for this lecture,
  treat that HTML as the AUTHORITATIVE Combined Theory + PYQ source for the deck.
  Theory slides come from the concept sections of the HTML.
  Examiner-trap and common-mistake slides may be summarised from the HTML.
  PYQ Practice slides must follow Section F's Actual PYQ Set rule.
  Do NOT copy long HTML paragraphs verbatim.
  Convert theory into slide-friendly bullets, examples, comparisons, diagrams, and speaker notes.
  Convert PYQ discussion into question-only slides plus answer/explanation slides.

DECK GOAL: COMBINED THEORY + PYQ in ONE deck — a single lecture slot covers both,
because there was no room for a separate PYQ lecture. Split the deck into two halves:
  FIRST teach the core concepts CONCISELY — lead with the CRITICAL & CONFUSING concepts
  flagged in Section F, disambiguate look-alike pairs, one tight worked example each. Do
  NOT pad the theory; you must leave room for the PYQ drill.
  THEN spend the back half on the REAL previous-year questions provided below — show the
  actual questions on slides, then model answers with the examiner trap for each.
Cover every concept the analysis names, but stay tight so both halves fit one deck.

SLIDE COUNT -- DETERMINE BY CONTENT, NOT A FIXED NUMBER:
  Do not compress or stretch the topic to hit a fixed slide count.
  For a single-concept Combined Theory + PYQ deck, typical deck size is 14-22 slides.
  For multi-concept Combined Theory + PYQ decks, typical deck size is 20-32 slides.
  The actual count depends on concept density, number of source PYQs, unique traps,
  and answer-slide grouping.
  Never stretch a small concept only to reach a large slide count.
  Never cram theory and PYQ answers into unreadable slides by shrinking fonts or overcrowding.

  Combined deck rhythm:
    * Start with Title, Agenda, Prior Knowledge Check.
    * Use concise theory slides first.
    * Add Common Mistakes immediately after theory.
    * Use a PYQ Practice block in the back half.
    * End with Key Takeaways and Exit Ticket.
    * CRITICAL/HIGH subtopics listed in Section D get dedicated slides.
    * MEDIUM subtopics may share a slide unless they have multiple distinct cases.
    * If a subtopic has MULTIPLE DISTINCT CASES (e.g. valid identifiers, invalid identifiers, keywords, and comments),
      give EACH case its own slide or clearly separated section — never
      compress distinct cases into one bullet list just to save slides.
    * CRITICAL-priority subtopics (Section F) --> 2 slides: theory + worked example.
    * HIGH-priority subtopics --> 1 dedicated slide.
    * MEDIUM-priority subtopics --> 1 bullet on a shared slide, UNLESS that
      subtopic has multiple distinct cases (above), then give it its own slide too.
    * CONTINUATION (encouraged — do NOT cram): when one concept needs more room
      than a single slide allows (more than 3 bullets, or theory + worked example
      + an exam trap), SPLIT it across consecutive slides. Title the overflow slide
      "<SAME TOPIC> (contd...)" and add a small "...continue ->" marker bottom-right
      of the first slide so the flow is obvious. Two clean slides always beat one
      crowded slide — never shrink the font or exceed 3 bullets just to make it fit.
  Fixed-position slides (always present, regardless of total count):
    Title, Agenda, Prior Knowledge Check        -- start of deck
    Common Mistakes                         -- immediately after content slides
    PYQ Practice block:
      Use all 11 actual PYQs.
      First create 3-5 question-only slides, grouping questions by pattern.
      Then create grouped answer/explanation slides by concept pattern.
      Every actual PYQ must be visibly accounted for; no PYQ may be silently dropped.
      This block may contain 7-11 slides depending on grouping and readability.
    Key Takeaways, Exit Ticket              -- final two slides, in that order


EXPLAIN FOR UNDERSTANDING, NOT JUST RECALL (the most important rule here):
  A student must understand the concept by reading the slide ONCE, without
  the teacher's voice filling gaps. For every theory/definition slide:
    * Start with a one-line plain-English restatement ("In simple words: ...")
      — not just the textbook/jargon definition.
    * Follow with ONE tiny concrete example showing the concept in action
      (student_name, marks2, # comment, and invalid 2marks, a real value, a real before/after) — never leave
      a definition abstract with no example near it.
    * If two things are easily confused (e.g. break vs Break, spaces/special symbols vs underscore), show them side by side on a Two Column slide — never describe
      look-alike concepts on separate, disconnected slides.

================================================
SECTION C -- SLIDE OUTPUT FORMAT (USE EXACTLY)
================================================

+=======================================================+
SLIDE [n]: [SLIDE TITLE IN CAPS]
Layout     : [Full-bleed Dark / Left Icon+Text / Two Column /
              Code Card / Callout Box / Exam Spotlight /
              3-Icon Grid / Warning Banner]
Background : [#0D1B2A or #F0F4F8]
Title font : Montserrat Bold -- 44 pt on body slides / 54 pt on the Title slide
Body font  : Calibri 28 pt Regular
-------------------------------------------------------
VISUAL ELEMENT: [icon/shape/code card/diagram on this slide]

[Bullet 1 -- max 10 words]  (blue circle = definition)
[Bullet 2 -- max 10 words]  (green circle = tip)
[Bullet 3 -- max 10 words]  (red circle = warning)

TOPIC-SPECIFIC EXAMPLE CARD RULE:
  * Every Combined Theory + PYQ PPT deck must include at least one topic-specific example card.
  * Use only examples from the current lecture topic.
  * Keep the example short enough for one Code Card slide.
  * For a conceptual topic, use a labelled visual, comparison, or valid-vs-invalid card instead of forcing unrelated code.
  * Place this card in the theory half, after the first concept explanation slide and before Common Mistakes.

IDENTIFIER + COMMENT CODE CARD -- paste inside dark card:
  +---------------------------------------------------------+
  |  student_name = "Aarav"   # valid identifier           |
  |  marks2 = 95              # digit allowed after first  |
  |                                                         |
  |  # 2marks = 95            # invalid: starts with digit |
  +---------------------------------------------------------+
  VISUAL LABELS:
    student_name -> valid identifier
    marks2       -> valid identifier
    # comment    -> ignored by interpreter
    2marks       -> invalid identifier

VALID VS INVALID COMPARISON CARD (use if clearer than code):
  Valid: name | student_name | marks2 | Break
  Invalid: 2marks | user name | user@2 | break
  Note: Python is case-sensitive. break is a keyword, but Break is not.

DIAGRAM SLIDES: describe shapes, arrows, labels, layout
-------------------------------------------------------
SPEAKER NOTES: [2-3 sentences for teacher -- NOT on slide.
Real-life analogy / Did You Know fact / exam tip / story.
EXCEPTION -- on Exit Ticket slides the notes carry the COMPLETE answer + explanation; PYQ Practice answer slides instead show the full solution + explanation + Critical Trap directly ON the slide (never in notes) (code may span many lines).]
+=======================================================+

================================================
SECTION D -- MANDATORY SLIDE SPECIFICATIONS
================================================

TITLE SLIDE (slide 1)
  Layout     : Full-bleed Dark (#0D1B2A background)
  Topic name : "Python basics, tokens, identifiers and comments Theory + PYQ" -- 54 pt Bold Cyan Electric (#00D4FF)
  Sub-line 1 : "XII CS Computer Science" -- 32 pt White
  Sub-line 2 : "CBSE Board | Lecture 1" -- 24 pt Slate Mist (#C9D4E0)
  Motif      : semi-transparent { } bracket centred background (15% opacity)

AGENDA (slide 2)
  Layout     : Left Icon+Text
  One row per subtopic below: icon-circle + subtopic name + time estimate

PRIOR KNOWLEDGE CHECK (slide 3)
  Layout     : Callout Box centred
  Single question in large rounded rectangle
  Badge      : "Think -> Pair -> Share" top-right
  Speaker notes: real-life analogy (NOT on slide)

CONTENT SLIDES (as many as the SLIDE COUNT rules in Section B require)
  Subtopics to cover (allocate slide count by PYQ FOCUS priority in Section F):
  • Python basics, tokens, identifiers and comments

  Layout rules:
  * Avoid repeating the same layout twice in a row unless the second slide is a continuation, paired worked example, or necessary code-tracing slide. Clarity is more important than artificial layout rotation.
  * Theory    --> Callout Box for definition + Left Icon+Text for bullets
  * Examples  --> Code Card (dark card, Courier New 24 pt, keywords Cyan Electric)
  * Comparisons / look-alike concepts --> Two Column layout
  * Apply the EXPLAIN FOR UNDERSTANDING rule (Section B) to every theory slide
  * CRITICAL priority subtopics --> 2 slides (theory + worked example)
  * HIGH priority subtopics     --> 1 dedicated slide
  * MEDIUM priority subtopics   --> 1 bullet on a shared slide, UNLESS it has
    multiple distinct cases (Section B), then give it its own slide too

COMMON MISTAKES & EXAMINER TRAPS (right after all content slides)
  Layout     : Warning Banner
  Accent     : left thick border #E74C3C (4 pt) on each bullet card
  Title      : "DON'T MAKE THESE MISTAKES" -- 44 pt Bold Red
  EXACTLY 3 bullets -- specific PYQ traps with red alert icon

PYQ PRACTICE -- THIS IS THE PYQ HALF OF A COMBINED THEORY+PYQ DECK.
The theory slides above already taught the concept; now drill the REAL previous-year
questions.

  STEP 1 -- QUESTION-ONLY SLIDES:
    QUESTION-ONLY SLIDE RULE:
    * Use 3-5 Exam Spotlight question-only slides.
    * Group questions by concept pattern.
    * Never force 11 questions into only 2-3 slides if readability suffers.
    * Keep all visible text at or above required font size.
    * If a question with options becomes crowded, split into another question-only slide.
    * Readability is more important than reducing slide count.
    * Show all 11 actual PYQs.
    * Group by: identifiers; keywords; comments;
      Python basics / file extension / high-level language; implicit variable declaration.
    * Show question text, real year badge, and marks badge.
    * Do not show answer, explanation, or trap on question-only slides.

  STEP 2 -- GROUPED ANSWER / EXPLANATION SLIDES:
    * Create grouped answer slides by concept pattern, not necessarily one slide per question.
    * Each answer slide may cover 2-3 related 1M questions if readable.
    * For each PYQ shown, include final answer, one-line explanation, marking point,
      and a "Critical Trap" callout directly ON the slide.
    * If one slide becomes crowded, split it into continuation slides.
    * Speaker notes contain teacher dialogue, timing advice, and peer-marking guidance.
  Placement  : after Common Mistakes and before Key Takeaways

KEY TAKEAWAYS (second-to-last slide)
  Layout     : 3-Icon Grid (dark #0D1B2A background -- matches title)
  3 equal columns: large icon + 1-line heading (28 pt Bold) + 1-line summary (24 pt)
  EXACTLY 3 takeaways

EXIT TICKET (last slide)
  Layout     : Callout Box centred
  EXACTLY 1 MCQ or fill-in-the-blank -- question 32 pt, options 28 pt
  Timer badge: "60 seconds" top-right (Cyan Electric)
  ANSWER + EXPLANATION ONLY IN SPEAKER NOTES

================================================
SECTION E -- ENGAGEMENT RULES (MIN 2 IN SPEAKER NOTES)
================================================

1. Prior Knowledge Check slide: real-life analogy -- NOT textbook language
2. One slide: "Did You Know?" fun fact in speaker notes
3. One code slide: "Guess the Output?" -- ask class before revealing
4. Colour-coded bullets: red = warning, green = tip/example, blue = definition
5. Common Mistakes slide: one "Examiner Trap" with specific wrong answer students typically write

================================================
SECTION F -- PYQ FOCUS (WEIGHT SLIDES BY EXAM IMPORTANCE)
================================================

Board exam appearances: 11 times (2021-2025) | Total marks tested: 11M

DECK INTENT: build this as the POLISHED, EXAM-FOCUSED version of the study
notes — cover EVERY examiner-tested concept below (not just definitions),
and lead with the CRITICAL + CONFUSING concepts, giving them the most slide time.

TOP PRIORITY -- CRITICAL & CONFUSING CONCEPTS (open the content with these):
  ! Python basics tokens identifiers and comments — asked as MCQ/Short Answer; 11x repeated --> own concise theory focus + PYQ drill priority; if it has a look-alike, use a Two-Column 'X vs Y' compare slide.

SUBTOPIC PRIORITY (allocate slide count by this ranking — see SLIDE COUNT rules in Section B):
  CRITICAL --> concise concept teaching first, then highest-priority PYQ drill
    * Python basics tokens identifiers and comments — 11x in exams, 11M total (years: 2025, 2024, 2023)

===========================================
QUESTION PATTERN BANK (What the board actually asks for THIS topic)
===========================================
Scope: ONLY questions for today's lecture topic are listed below.
DO NOT import questions from other topics or chapters.
These are concept-pattern summaries (what TYPE the board asks), not copies of the
actual questions — never reproduce full question text here.

### Concept: Python basics tokens identifiers and comments
  Pattern: MCQ=7, Short Answer=4 | Marks: 1M=11 | Total: 11 questions
  [MCQ] [1M] [Easy]
    → Invalid identifier recognition
  [MCQ] [1M] [Easy]
    → Python file extension
  [MCQ] [1M] [Easy]
    → Single-line comment symbol
  [Short Answer] [1M] [Easy]
    → True/False: implicit variable declaration
  [Short Answer] [1M] [Easy]
    → True/False: identifier meaning
  [MCQ] [1M] [Easy]
    → Python keyword recognition
  [Short Answer] [1M] [Easy]
    → True/False: comments are not executed
  [Short Answer] [1M] [Easy]
    → True/False: Python as a high-level language
  [MCQ] [1M] [Easy] × 3
    → Valid identifier recognition


===========================================
IMPORTANCE ANALYSIS (allocate teaching time by this ranking)
===========================================
| Rank | Concept | Score | Times Tested | Total Marks | Recent Years | Priority |
|------|---------|-------|-------------|-------------|--------------|----------|
| 1 | Python basics tokens identifiers and comments | 42 | 11 | 11M | 2025, 2024, 2023 | CRITICAL |

EXAMINER FINGERPRINT -- TRAPS TO COVER INTERNALLY

Use this section only for internal slide planning. Do not print this
heading or these internal labels on slides.

For this lecture, the deck must strongly cover these traps:

1. Confusing Python keywords with valid identifiers.
   - Wrong thinking: "Any word can be used as a variable name."
   - Correct thinking: Python keywords cannot be used as identifiers.
2. Confusing lowercase keywords with capitalized words.
   - Wrong thinking: "Break and break are both keywords."
   - Correct thinking: Python is case-sensitive; break is a keyword, Break is not.
3. Forgetting that identifiers cannot start with a digit.
   - Wrong thinking: "2user is valid because it contains letters."
   - Correct thinking: Identifiers may contain digits, but cannot start with a digit.
4. Confusing underscore with space or special symbols.
   - Wrong thinking: "user 2 or user@2 is valid."
   - Correct thinking: user_2 is valid; spaces and @ are not allowed in identifiers.
5. Forgetting that # starts a single-line comment.
   - Wrong thinking: "// is used for single-line comments in Python."
   - Correct thinking: Python uses # for single-line comments.
6. Thinking comments are executed by the interpreter.
   - Wrong thinking: "Comments affect program output."
   - Correct thinking: Comments are ignored by the interpreter.
7. Thinking variables must be declared before assignment in Python.
   - Wrong thinking: "Python requires variable declaration first."
   - Correct thinking: Variable declaration is implicit in Python.
8. Forgetting that Python source files use .py extension.
   - Wrong thinking: ".exe or .p is the default Python file extension."
   - Correct thinking: Python source files commonly use .py.

* Common Mistakes slide must select the top 3 traps from this Examiner
  Fingerprint list.
* PYQ Practice slides must together cover at least 4 traps from the Examiner Fingerprint list.
* Content slides must teach the traps before practice slides test them.

ACTUAL PYQ SET FOR PRACTICE
  Source pool has 11 PYQs.
  Since the pool has 15 or fewer questions, use all 11 actual PYQs.
  Do not replace these with newly framed representative questions.
  Do not compress by dropping, replacing, paraphrasing, or hiding actual PYQs.
  All 11 actual PYQs must appear visibly in the question-only block.
  Grouping related answers on the same answer/explanation slide is allowed only
  for layout efficiency, provided every PYQ still gets:
    - final answer
    - one-line explanation
    - marking point
    - Critical Trap
  Order questions Easy -> Tough; within difficulty, order 1M -> 2M -> 3M -> 4/5M.
  Every PYQ must be visibly accounted for in the question-only block
  and in grouped answer/explanation coverage by concept pattern.
  Each PYQ needs a final answer, one-line explanation, marking point,
  and Critical Trap directly on an answer/explanation slide.
  Do not create substitute or compressed questions for this small source pool.

  Pattern 1. [1M] [Easy/MCQ] Concept: Invalid identifier recognition | source example: 2021
  ```
  Find the invalid identifier from the following:
  a) none
  b) address
  c) Name
  d) pass
  ```
  Pattern 2. [1M] [Easy/MCQ] Concept: Python file extension | source example: 2021
  ```
  Which one of the following is the default extension of a Python file?
  a) .exe
  b) .p++
  c) .py
  d) .p
  ```
  Pattern 3. [1M] [Easy/MCQ] Concept: Single-line comment symbol | source example: 2021
  ```
  Which of the following symbol is used in Python for single line comment?
  a) /
  b) /*
  c) //
  d) #
  ```
  Pattern 4. [1M] [Easy/Short Answer] Concept: Implicit variable declaration | source example: 2022
  ```
  State True or False:
  "Variable declaration is implicit in Python."
  ```
  Pattern 5. [1M] [Easy/Short Answer] Concept: Identifier meaning | source example: 2023
  ```
  State True or False.
  "Identifiers are names used to identify a variable, function in a program".
  ```
  Pattern 6. [1M] [Easy/MCQ] Concept: Python keyword recognition | source example: 2023
  ```
  Which of the following is a valid keyword in Python ?
  (a) false
  (b) return
  (c) non_local
  (d) none
  ```
  Pattern 7. [1M] [Easy/Short Answer] Concept: Comments are not executed | source example: 2023
  ```
  State True or False.
  "Comments are not executed by interpreter."
  ```
  Pattern 8. [1M] [Easy/Short Answer] Concept: Python as high-level language | source example: 2024
  ```
  State True or False:
  "Python is a high level language."
  ```
  Pattern 9. [1M] [Easy/MCQ] Concept: Valid identifier recognition | source example: 2024
  ```
  Which of the following is a valid identifier ?
  (A) break
  (B) global
  (C) 2bin
  (D) except
  ```
  Pattern 10. [1M] [Easy/MCQ] Concept: Valid identifier recognition | source example: 2024
  ```
  Identify the valid Python identifier from the following :
  (A) 2user
  (B) user@2
  (C) user_2
  (D) user 2
  ```
  Pattern 11. [1M] [Easy/MCQ] Concept: Valid identifier vs keyword/case sensitivity | source example: 2025
  ```
  Which of the following is the correct identifier?
  (A) global
  (B) Break
  (C) def
  (D) with
  ```

SLIDE WEIGHTING RULE:
  CONFUSING/CRITICAL concepts --> concise concept teaching first, then highest-priority PYQ drill;
                                  use 'X vs Y' compare slides for look-alikes
  HIGH subtopics     --> own slide
  MEDIUM subtopics   --> 1 bullet max on a shared slide
  Every concept named in the QUESTION PATTERN BANK above MUST appear on a slide —
  a concept the board has actually tested may NEVER be dropped to save slides.

SOURCE POOL RULE:
  Because this source pool has only 11 PYQs, use all 11 actual PYQs.
  Do not drop, replace, paraphrase, or hide any actual PYQ.
  Every PYQ must appear visibly in the question-only block.
  Grouping related answers is allowed only for layout efficiency.
  Compression by omission is allowed only when source pool has more than 15 PYQs.
  If the pool has 15 or fewer PYQs, every actual PYQ must be included and accounted for.
  If a question is reproduced verbatim, show its real year and marks.
  Never fabricate a year, section, paper, or marks badge.

PYQ PRACTICE QUESTION RULE:
  Use all 11 actual PYQs from the source pool.

  QUESTION-ONLY SLIDE RULE:
  Use 3-5 Exam Spotlight question-only slides.
  Group questions by concept pattern.
  Never force 11 questions into only 2-3 slides if readability suffers.
  Keep all visible text at or above required font size.
  If a question with options becomes crowded, split into another question-only slide.
  Readability is more important than reducing slide count.

  Create:
    * 3-5 question-only slide(s), grouped by concept pattern
    * grouped answer/explanation slide(s), grouped by concept pattern
  The authoritative count is 11 actual PYQs, not a fixed number of slides.
  The PYQ block may contain 7-11 slides total depending on grouping and readability.
  Never shrink font below the required size to fit more answers.
  Split into continuation slides whenever needed.

  PYQ ANSWER VISIBILITY RULE:
  Question-only slides:
    - Show only question text, marks badge, and real year badge.
    - No answer, explanation, or trap on the slide.
    - Speaker notes may contain the answer for teacher reference.
  Answer/explanation slides:
    - Show final answer directly ON the slide.
    - Show one-line explanation directly ON the slide.
    - Show marking point directly ON the slide.
    - Show "Critical Trap" callout directly ON the slide.
    - Speaker notes carry teacher dialogue, timing advice, and peer-marking guidance.

NO-FABRICATION RULE:
  Use all 11 actual PYQs from the source pool.
  If the source pool has 15 or fewer PYQs, every actual PYQ must be included and accounted for.
  If a PYQ is reproduced verbatim, show its real year and marks.
  If the source pool has more than 15 PYQs and compression is necessary, representative
  questions may be used only after the highest-yield 15 are fully discussed.
  Representative questions must be labelled "Representative PYQ-pattern question"
  and must not show fake year or fake marks.
  Never fabricate a previous-year question, year, section, paper, or marks badge.
  Never silently drop a source PYQ.

================================================
SECTION G -- QUALITY CHECKLIST (VERIFY BEFORE OUTPUT)
================================================

Visual Checks:
  [ ] Title font >= 44 pt on every slide
  [ ] Body font >= 28 pt on every slide
  [ ] Code font >= 24 pt inside dark card only
  [ ] No font below 24 pt anywhere
  [ ] Every slide has icon, shape, code card, or diagram
  [ ] No unnecessary repeated layout; continuation, paired worked-example, and necessary code-tracing slides may repeat layout.
  [ ] Sandwich: dark Title -> light content -> dark Key Takeaways -> light Exit Ticket
  [ ] { } bracket motif on every content slide
  [ ] NO accent lines under titles
  [ ] NO full-width colour bars or stripes
  [ ] NO cream/beige backgrounds
  [ ] Bullets left-aligned (titles centred only)
  [ ] ONE clear focal point per slide (one hero element, one accent moment)
  [ ] Objects snapped to the grid -- tops/left edges aligned, nothing free-floating
  [ ] Accent colour <= 10% of slide area; cards use 6-8% tints, not saturated fills
  [ ] Every slide's visual carries meaning (no decorative icon-circles / clip-art)
  [ ] At least 60% of each content slide is background + breathing space

Content Checks:
  [ ] CRITICAL/HIGH subtopics in Section D have dedicated slides
  [ ] MEDIUM subtopics are covered on shared slides unless they have multiple
      distinct cases
  [ ] Multi-case subtopics (valid names, invalid names, keywords, and comments) have EACH case
      covered, not compressed into one slide
  [ ] Every theory slide has a plain-English restatement AND a concrete example
  [ ] No slide has more than 3 bullets
  [ ] No bullet longer than 10 words
  [ ] Every code example on its own Code Card slide
  [ ] Common Mistakes slide has EXACTLY 3 examiner traps (red accent)
  [ ] All 11 actual PYQs are used/accounted for.
  [ ] For source pools of 15 or fewer PYQs, all actual PYQs are included.
  [ ] Question-only block contains 3-5 slides.
  [ ] No question-only slide is overcrowded.
  [ ] MCQ options remain readable without shrinking fonts.
  [ ] Answer/explanation slides are grouped by concept pattern.
  [ ] Every PYQ has visible answer/explanation coverage.
  [ ] No actual PYQ is silently dropped.
  [ ] Question-only slides show no answer, no explanation, and no trap.
  [ ] Answer slides show final answer + explanation + marking point + Critical Trap directly on slide.
  [ ] PYQ Practice slides ordered easiest-to-hardest
  [ ] Key Takeaways slide has EXACTLY 3 takeaways in 3-Icon Grid layout
  [ ] Exit Ticket has 1 question with answer ONLY in speaker notes
  [ ] All speaker notes include teacher dialogue (EXCEPT PYQ Practice answer slides (answer is ON the slide, not in notes) & Exit Ticket (answer in notes) -- Section C)
  [ ] Minimum 2 engagement techniques across speaker notes

Layout Safety Checks:
  [ ] Every slide uses 16:9 widescreen canvas
  [ ] All objects keep at least 0.35 inch margin from slide edges
  [ ] Title stays within y=0.35-1.15 inch and wraps to max 2 lines
  [ ] Body starts at y >= 1.45 inch; large cards/callouts at y >= 1.55 inch
  [ ] Badges stay in the top-right badge zone and never touch title/body
  [ ] No text, badge, icon, card, code block, or diagram overlaps another object
  [ ] No PowerPoint auto-fit has reduced required font sizes
  [ ] Continuation slides are used whenever content would otherwise crowd
  [ ] Rendered slide images have no clipped, hidden, overlapping, or tiny text

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