docs: def extract_version(txt):
      """This function tries to extract the version from the help text of any
      program."""
      words = txt.replace(',', ' ').split()
      version = None
      for x in reversed(words):
          if len(x) > 2:
              if x[0].lower() == 'v':
                  x = x[1:]
              if '.' in x and x[0].isdigit():
                  version = x
                  break
      return version