code: def parse(cls, parser, text, pos):  # pylint: disable=W0613
          
          if not text.strip():
              return text, SyntaxError("Invalid value")
  
          class Rule(object):
              grammar = attr('value', SpiresSimpleValue), omit(re.compile(".*"))
  
          try:
              tree = pypeg2.parse(text, Rule, whitespace="")
          except SyntaxError:
              return text, SyntaxError("Expected %r" % cls)
          else:
              r = tree.value
  
          if r.value.lower() in ('and', 'or', 'not'):
              return text, SyntaxError("Invalid value %s" % r.value)
  
          return text[len(r.value):], r
docs: Match simple values excluding some Keywords like 'and' and 'or