Give an Excel custom skill a Python script

Download the exercise (ZIP)

Use a prepared Copilot skill to check six fictional expenses, change one dollar, and run the same Python script again. You do not need to write Python.

• python-skills-practice.xlsx — the starting workbook.
• expense-check-python/ — the complete skill folder, containing SKILL.md and scripts/check_expenses.py.
• practice-prompts.txt — the prompts to copy into Copilot.
• README.md — these instructions.

1. Extract the ZIP and open python-skills-practice.xlsx.
2. In Copilot settings, open Manage skills (or Manage plugins & skills), then Custom skills. Open the OneDrive skills folder; create it if needed.
3. Copy the entire expense-check-python folder into it. Inside the copied folder, SKILL.md should sit beside scripts. Let OneDrive sync, refresh the skill list, and enable the skill if needed.
4. Send PASS 1 from practice-prompts.txt in the practice workbook.
5. Check the new ExpenseCheck sheet: Food ($600 over budget) and Repairs ($900 over) should say Yes. Supplies is exactly $500 over, so it is No.
6. Change Data!C7 from 1500 to 1501, then send PASS 2. Supplies should now say Yes, bringing the count from two to three.

ExpenseCheck is a snapshot. Rerun the skill after changing Data.

You need Copilot workbook editing, Custom skills, and a Python execution tool available in that Copilot session. The skill stops if Python cannot run. This workflow does not require a GitHub account or a local Python installation, and it is separate from Python in Excel's =PY() worksheet feature.

Clear Data!B10 (Repairs budget), then send OPTIONAL CHECK from the prompts file. The script should stop and identify the missing budget. Any existing ExpenseCheck sheet is now an older snapshot. Restore B10 to 1000 and C7 to 1500, then send PASS 1 to return to the starting example.

The rule is Actual minus Budget > 500. All data and the threshold are fictional teaching examples.

For the earlier JSON lesson, see the separate article and exercise.