Finish a small, explainable Python tool
See this course’s project requirements
Build a supply-kit calculator, check it with five test cases, and explain how to use it. Combine the work you complete across the six lessons.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
What to include
- State numeric input rules and invalid-input behavior.
- Include a working function, conditional guard and loop over a list.
- Show original, changed, empty and invalid-input reasoning.
- Retain five explicit tests with expected results.
- Provide complete code, expected output and a handoff note.
Review and revise
Use these criteria to check your work and choose what to improve.
- Correctness: valid quantities produce independently checked kit counts.
- Reasoning: traces explain assignment, branches and repeated work.
- Testing: normal and invalid cases support the claimed behavior.
- Handoff: supported inputs and limitations are clear.
Want more background?
The idea in everyday life
Your final tool summarizes a few workshop inventories. Its value is not the number of lines it contains but whether someone can understand the input, predict the output and recognize unsupported cases. You already have the function, loop reasoning and tests. This lesson joins those outputs without adding accounts, external packages or file-system access.
A finished small program includes its operating instructions and known limits.
One step at a time.
Use the sample or information you have permission to use. Keep your work as you go. You can pause between steps.
- 1
Copy the guarded complete_kits function from the previous lesson into a single program. Preserve its input contract, including the restriction to whole-number quantities, in a short comment or accompanying note.
- 2
Add the sample inventory list [23,12,0]. Use a loop to call the function for each count with four supplies per kit. Print the input and result together so their relationship stays visible.
- 3
Add a separate invalid-input demonstration such as complete_kits(8,0). Label None as invalid configuration in your explanation rather than reporting it as zero kits.
- 4
Reuse the five tests from your debugging record. Trace the complete program once and, if an available Python 3 environment is permitted, run it. Paper completion includes an exact expected-output transcript.
- 5
Write a handoff note explaining which list and per-kit value may be changed, how to check outputs, and which inputs remain unsupported. Finish with one proposed improvement and the test it would need.
See how it works.
Fictional example: the completed workshop summary is self-contained.
def complete_kits(supplies, per_kit):
if supplies < 0 or per_kit <= 0:
return None
return supplies // per_kit
inventories = [23, 12, 0]
for amount in inventories:
print(amount, "supplies ->", complete_kits(amount, 4), "kits")
print("Invalid example:", complete_kits(8, 0))The three inventory lines report 5, 3 and 0 kits. The final line reports None. This demonstration makes the invalid case visible without changing the valid inventory list. The handoff says that the program does not accept text such as "many" and does not reserve stock across different sessions.
Did you cover these?
- Complete program contains definition and calls.
- All five previous tests are retained.
- Handoff explains None and whole-number input limits.
What to finish
One complete program, expected-output transcript, reused tests and a short handoff note.
Watch for this
Claiming a classroom example is production-ready or hiding input assumptions.
How can I tell I understand it?
Another reader can change one supported input and predict the new output.
Quick knowledge check
Answer all 3 questions. Get at least 2 right and the lesson completes automatically.
You’ll get an explanation for each answer. Signed in? Your results save to your account.
Pass the check. We’ll save the progress.
Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.
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Tools and templates
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Sources and further reading
Explore the references behind this lesson.
Source & access notes · checked 2026-09-10
Opened the course overview and Week 0 page; verified coverage of variables, conditionals, loops, exceptions and testing. Optional deeper study, not a source of copied exercises.
Access: OpenCourseWare is free to read/watch. External assignment submission requires an edX account; optional verified/professional certificates use separate enrollment and may cost money. No Harvard affiliation or credit is offered here.
Reuse: Linked for reference. Examples, activities and assessments here are original; free access alone does not grant permission to reuse source text or branding.
Source & access notes · checked 2026-09-10
Opened official tutorial covering if, for, range and function definitions; examples use stable Python 3 syntax.
Access: Free public reading; no account or certificate is required for this Life Starter course.
Reuse: Linked for reference. Examples, activities and assessments here are original; free access alone does not grant permission to reuse source text or branding.
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