docs: def replace_lines(regexer, handler, lines):
      """Uses replacement handler to perform replacements on lines of text
  
      First we strip off all whitespace
      We run the replacement on a clean 'content' string
      Finally we replace the original content with the replaced version
      This ensures that we retain the correct whitespace from the original line
      """
      result = []
      for line in lines:
          content = line.strip()
          replaced = regexer.sub(handler, content)
          result.append(line.replace(content, replaced, 1))
      return result