csv.writer vs csv.DictWriter

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Accepted Answer

csv.writer.writerow(row) expects a sequence: ['Alice', 30, 'NY']. You control column order by the order of values in the list. csv.DictWriter is initialized with fieldnames=['name','age','city'] and writerow() takes a dict: {'name':'Alice','age':30,'city':'NY'}. DictWriter maps dict keys to the declared column order, so you don't have to worry about getting the sequence right. DictWriter also gives you writeheader() to write the column names as the first row automatically. For structured data where rows come as dicts (e.g., from a database query), DictWriter is the natural fit.