Python script to add a column to cvs file with a default value

add-column-to-cvs.py

#!/usr/bin/env python3

import csv
import sys

# Read command line arguments
field_name = sys.argv[1]
default_value = sys.argv[2]

# Open the input CSV file
with open('input.csv', 'r') as input_file:
  # Create a CSV reader to parse the input file
  reader = csv.reader(input_file)

  # Open the output CSV file
  with open('output.csv', 'w', newline='') as output_file:
    # Create a CSV writer for the output file
    writer = csv.writer(output_file)

    # Write the header row
    header_row = next(reader)
    header_row.append(field_name)
    writer.writerow(header_row)

    # Write the data rows
    for row in reader:
      row.append(default_value)
      writer.writerow(row)