November 12, 2026 | macOS | Python 3.14.9
Fictional practice inputs. Commands run from the extracted practice packs.

$ python3 csv_map_headers.py blocked.csv schema-a.csv schema-b.csv candidate.csv
Exit 1
STOP: candidate.csv: required order_id or amount header missing

$ python3 csv_map_headers.py present.csv schema-a.csv schema-b.csv candidate.csv
Exit 0
schema-a.csv: 1 data record(s)
schema-b.csv: 1 data record(s)
candidate.csv: 1 data record(s)
Output data records: 3

$ python3 csv_map_headers.py combined.csv schema-a.csv schema-b.csv schema-c.csv
Exit 0
schema-a.csv: 1 data record(s)
schema-b.csv: 1 data record(s)
schema-c.csv: 1 data record(s)
Output data records: 3

present.csv final row: ['candidate.csv', '003', '30.00', '', 'complete']

combined.csv final row: ['schema-c.csv', '003', '30.00', '', 'missing region']