code: def sanitize_filename(filename):
      
      sanitized_filename = re.sub(r'[/\\:*?"<>|]', '-', filename)
      sanitized_filename = sanitized_filename.replace('&', 'and')
      sanitized_filename = sanitized_filename.replace('"', '')
      sanitized_filename = sanitized_filename.replace("'", '')
      sanitized_filename = sanitized_filename.replace("/", '')
      sanitized_filename = sanitized_filename.replace("\\", '')
  
      # Annoying.
      if sanitized_filename[0] == '.':
          sanitized_filename = u'dot' + sanitized_filename[1:]
  
      return sanitized_filename
docs: Make sure filenames are valid paths.
  
      Returns:
          str: