code: def parse_scalar_type_definition(lexer: Lexer) -> ScalarTypeDefinitionNode:
      
      start = lexer.token
      description = parse_description(lexer)
      expect_keyword(lexer, "scalar")
      name = parse_name(lexer)
      directives = parse_directives(lexer, True)
      return ScalarTypeDefinitionNode(
          description=description, name=name, directives=directives, loc=loc(lexer, start)
      )
docs: ScalarTypeDefinition: Description? scalar Name Directives[Const]?