Attempt before opening ../.. /solutions/L07.md.
1. Complete the story:
   run_report.py calls ______ with channel ______.
   report.py returns a ______; the caller turns it into ______ text.
2. Predict Social cost_cents, enquiries and row count.
3. A fresh folder calls build_report before initialise. Explain the failure.
4. Unknown channel receives 400. /missing receives 404. Explain the difference.
5. Locate a function definition, an import and a call. Explain their jobs.
