old_contents: #!/usr/bin/python3
  
  import argparse
  
  if __name__ == '__main__':
  
      # Boilerplate to allow running as script directly. Avoids error below:
      # SystemError: Parent module '' not loaded, cannot perform relative import
      # See http://stackoverflow.com/questions/2943847/
      if __package__ is None:
          import sys
          import os
          abspath = os.path.abspath(__file__)
          parent_dir = os.path.dirname(os.path.dirname(abspath))
          sys.path.insert(0, parent_dir)
          from whoarder.clippings import Clippings
          del sys, os
  
      parser = argparse.ArgumentParser(description="whoarder converts Kindle \
                          'My Clippings.txt' files to more pleasant HTML.")
      parser.add_argument('source',
                          help='Path to the source file, stored by Kindle in \
                          /Media/Kindle/documents/My Clippings.txt.')
      parser.add_argument('destination',
                          help='Target HTML file. If omitted, a .html bearing \
                          the same name as the input .txt file will be used.',
                          nargs='?', default=None)
      args = parser.parse_args()
  
      clippings = Clippings(args.source, args.destination)
      clippings.export_clippings()
      print('Successfully wrote ' + clippings.dest + "\n")
  
new_contents: #!/usr/bin/env python3
  
  import argparse
  
  if __name__ == '__main__':
  
      # Boilerplate to allow running as script directly. Avoids error below:
      # SystemError: Parent module '' not loaded, cannot perform relative import
      # See http://stackoverflow.com/questions/2943847/
      if __package__ is None:
          import sys
          import os
          abspath = os.path.abspath(__file__)
          parent_dir = os.path.dirname(os.path.dirname(abspath))
          sys.path.insert(0, parent_dir)
          from whoarder.clippings import Clippings
          del sys, os
  
      parser = argparse.ArgumentParser(description="whoarder converts Kindle \
                          'My Clippings.txt' files to more pleasant HTML.")
      parser.add_argument('source',
                          help='Path to the source file, stored by Kindle in \
                          /Media/Kindle/documents/My Clippings.txt.')
      parser.add_argument('destination',
                          help='Target HTML file. If omitted, a .html bearing \
                          the same name as the input .txt file will be used.',
                          nargs='?', default=None)
      args = parser.parse_args()
  
      clippings = Clippings(args.source, args.destination)
      clippings.export_clippings()
      print('Successfully wrote ' + clippings.dest + "\n")
  
subject: Replace hashbang with /usr/bin/env python3 for better portability