code: def _clean_characters(x):
      
      if not isinstance(x, six.string_types):
          x = str(x)
      else:
          if not all(ord(char) < 128 for char in x):
              msg = "Found unicode character in input YAML (%s)" % (x)
              raise ValueError(repr(msg))
      for problem in [" ", ".", "/", "\\", "[", "]", "&", ";", "#", "+", ":", ")", "("]:
          x = x.replace(problem, "_")
      return x
docs: Clean problem characters in sample lane or descriptions.