Load data into ``CTfile`` object from string.
        
        :param str string: String containing data in ``CTfile`` format.
        :return: Instance of ``CTfile``.

def loadstr(cls, string):
        """Load data into ``CTfile`` object from string.
        
        :param str string: String containing data in ``CTfile`` format.
        :return: Instance of ``CTfile``.
        """
        try:
            string = string.decode('utf-8')
        except AttributeError:
            pass

        lexer = tokenizer(string)

        if cls.is_molfile(string):
            molfile = Molfile()

            try:
                molfile.update(json.loads(string))
            except ValueError:
                molfile._build(lexer)
            return molfile

        elif cls.is_sdfile(string):
            sdfile = SDfile()

            try:
                sdfile.update(json.loads(string))
            except ValueError:
                sdfile._build(lexer)
            return sdfile

        else:
            raise ValueError('Cannot determine the format of string.')