Clean the CSV. Keep every change explainable.
Fictional starter — replace with your own material.
Source: https://clankercloud.ai/templates/data-cleaning-checklist

Copy into Workspace yourself:

Clean the fictional CSV below into cleaned-records.csv and save cleaning-review.md in this Project. Preserve the original input. Treat record_id as text and keep leading zeros. Remove only exact duplicate rows, trim surrounding whitespace in customer_name, and never fill missing email or amount values.

Keep original event_date. Add normalized_event_date and date_status: valid ISO dates copy to normalized_event_date with status Valid; ambiguous dates keep normalized blank with status Ambiguous; impossible dates keep normalized blank with status Invalid. Do not guess the locale.

Report source rows, output rows, removed duplicates, changed fields, and unresolved issues. Total known numeric amounts across retained rows separately for USD and EUR; report blank amounts and clarify that these are not period-validated totals. Do not use exchange rates, contact customers, or overwrite a source file.

record_id,customer_name,email,amount,currency,event_date
001,Aster Studio,team@aster.example,120.00,USD,2026-09-01
002," Birch Works ",hello@birch.example,80.00,USD,2026-09-02
002," Birch Works ",hello@birch.example,80.00,USD,2026-09-02
003,Cedar Lab,,45.00,USD,2026-09-03
004,Dune Group,ops@dune.example,,USD,2026-09-04
005,Elm Studio,hi@elm.example,100.00,EUR,2026-09-05
006,Fern Works,team@fern.example,60.00,USD,09/06/2026
007,Grove Lab,hello@grove.example,25.00,USD,2026-09-31

Illustrative result:
Fictional expected reconciliation

Source rows: 8. Retained rows: 7. Exact duplicates removed: 1 (record 002).
Whitespace: retained 002 customer_name becomes Birch Works.
Missing email: 003. Missing amount: 004; remains blank.
Date issues: 006 Ambiguous; 007 Invalid. Their normalized dates remain blank and original strings remain present.
Known amounts: USD 330.00, plus one unresolved USD amount; EUR 100.00. No combined currency total.
These totals include retained rows with date issues and are not validated totals for a reporting period.

Review checklist:
- Eight input rows reconcile to seven retained rows and one exact duplicate removal.
- Leading zeros survive and the original file is unchanged.
- The blank amount remains blank; no zero or email was invented.
- Both date issues are visible and original date strings are preserved.
- Known amounts are USD 330.00 and EUR 100.00, with the missing USD amount disclosed.