code: def parse(cls, parser, text, pos):
          
          try:
              remaining_text, keyword = parser.parse(text, cls.grammar)
              if keyword.lower() == 'texkey':
                  parser._parsing_texkey_expression = True
              return remaining_text, InspireKeyword(keyword)
          except SyntaxError as e:
              parser._parsing_texkey_expression = False
              return text, e
docs: Parse InspireKeyword.
  
          If the keyword is `texkey`, enable the parsing texkey expression flag, since its value contains ':' which
          normally isn't allowed.