new_contents: #!/usr/bin/env python3
  """
  Usage: {script_name} INPUT_FILE OUTPUT_FILE
  
  Adds noise to the csv file given as input.
  """
  import random
  import sys
  from collections import deque
  
  
  def usage():
      print(__doc__.format(script_name=sys.argv[0].split("/")[-1]))
      sys.exit(0)
  
  
  def empty_lines(line_num):
      empty_count = 500*random.randint(1, 9)
      lines = list(random.randint(0, line_num - 1) for _ in range(empty_count))
      lines.sort()
      return deque(lines)
  
  
  def process_line(index, line, output, empty_lines):
      # Add random number in the beginning
      add_random_num = random.random() < .05
      # Add extra cell in the beginning
      extra_cell = random.random() < .05
  
      # Add empty lines
      if empty_lines:
          while empty_lines and empty_lines[0] == index:
              empty_lines.popleft()
              output.write("\n")
  
      if add_random_num:
          output.write(random.randint(0, 9))
  
      if extra_cell:
          output.write("{},".format(random.randint(0, 1000)))
  
      output.write(line)
  
  
  def main():
      if len(sys.argv) != 3:
          usage()
      input_file = open(sys.argv[1], "r")
      output_file = open(sys.argv[2], "w")
  
      line_num = sum(1 for _ in input_file)
      input_file.seek(0)
      empty = empty_lines(line_num)
  
      for index, line in enumerate(input_file):
          process_line(index, line, output_file, empty)
  
      input_file.close()
      output_file.close()
  
  main()
  
subject: Add scripts that adds noise to datasets