[Solved] Identify the error in this code that writes a CSV file using csv.DictWriter:import csv with open('output.csv', 'w') as f: writer = csv.DictWriter(f, fieldnames=['name', 'age']) writer.... | Python

Python - Structured Data Files

Identify the error in this code that writes a CSV file using csv.DictWriter:

import csv
with open('output.csv', 'w') as f:
    writer = csv.DictWriter(f, fieldnames=['name', 'age'])
    writer.writerow({'name': 'Alice', 'age': 30})
    writer.writerow({'name': 'Bob', 'age': 25})

ADictionaries passed to writerow must have string values only.

BFieldnames list should be a tuple, not a list.

CMissing call to writer.writeheader() before writing rows.

DThe file should be opened in binary mode 'wb'.

Step-by-Step Solution

Solution:

Step 1: Check DictWriter usage
DictWriter requires calling writeheader() to write the header row before writing data rows.
Step 2: Verify other parts
Opening file in text mode 'w' is correct in Python 3, fieldnames can be a list, and values can be int or str.
Final Answer:
Missing call to writer.writeheader() before writing rows. -> Option C
Quick Check:
Always call writeheader() before writerow() [OK]

Quick Trick: Call writeheader() before writing rows with DictWriter [OK]

Common Mistakes:

Forgetting writeheader() call
Opening file in binary mode unnecessarily
Thinking fieldnames must be tuple
Assuming all values must be strings

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Identify the error in this code that writes a CSV file using csv.DictWriter:

Step 1: Check DictWriter usage

Step 2: Verify other parts

Final Answer:

Quick Check:

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