How to use the parso.split_lines function in parso

- Having an indented block of code
        - Having some doctest code that starts with `>>>`
        - Having backticks that doesn't have whitespace inside it
        """
        def iter_relevant_lines(lines):
            include_next_line = False
            for l in code_lines:
                if include_next_line or l.startswith('>>>') or l.startswith(' '):
                    yield re.sub(r'^( *>>> ?| +)', '', l)
                else:
                    yield None

                include_next_line = bool(re.match(' *>>>', l))

        string = dedent(string)
        code_lines = split_lines(string, keepends=True)
        relevant_code_lines = list(iter_relevant_lines(code_lines))
        if relevant_code_lines[-1] is not None:
            # Some code lines might be None, therefore get rid of that.
            relevant_code_lines = [c or '\n' for c in relevant_code_lines]
            return self._complete_code_lines(relevant_code_lines)
        match = re.search(r'`([^`\s]+)', code_lines[-1])
        if match:
            return self._complete_code_lines([match.group(1)])
        return []

code = base.format(
        typename=name,
        field_names=tuple(fields),
        num_fields=len(fields),
        arg_list=repr(tuple(fields)).replace("u'", "").replace("'", "")[1:-1],
        repr_fmt=', '.join(get_var(u'_repr_template').format(name=name) for name in fields),
        field_defs='\n'.join(get_var(u'_field_template').format(index=index, name=name)
                             for index, name in enumerate(fields))
    )

    # Parse source code
    module = evaluator.grammar.parse(code)
    generated_class = next(module.iter_classdefs())
    parent_context = ModuleContext(
        evaluator, module, None,
        code_lines=parso.split_lines(code, keepends=True),
    )
    return ContextSet(ClassContext(evaluator, parent_context, generated_class))

This complete stuff is pretty weird, a generator would make
            a lot more sense, but probably due to backwards compatibility
            this is still the way how it works.

            The only important part is stuff in the ``state == 0`` flow,
            everything else has been copied from the ``rlcompleter`` std.
            library module.
            """
            if state == 0:
                sys.path.insert(0, os.getcwd())
                # Calling python doesn't have a path, so add to sys.path.
                try:
                    logging.debug("Start REPL completion: " + repr(text))
                    interpreter = Interpreter(text, [namespace_module.__dict__])

                    lines = split_lines(text)
                    position = (len(lines), len(lines[-1]))
                    name = get_on_completion_name(
                        interpreter._get_module_node(),
                        lines,
                        position
                    )
                    before = text[:len(text) - len(name)]
                    completions = interpreter.completions()
                except:
                    logging.error("REPL Completion error:\n" + traceback.format_exc())
                    raise
                finally:
                    sys.path.pop(0)

                self.matches = [before + c.name_with_symbols for c in completions]
            try:

code = _NAMEDTUPLE_CLASS_TEMPLATE.format(
        typename=name,
        field_names=tuple(fields),
        num_fields=len(fields),
        arg_list=repr(tuple(fields)).replace("u'", "").replace("'", "")[1:-1],
        repr_fmt='',
        field_defs='\n'.join(_NAMEDTUPLE_FIELD_TEMPLATE.format(index=index, name=name)
                             for index, name in enumerate(fields))
    )

    # Parse source code
    module = inference_state.grammar.parse(code)
    generated_class = next(module.iter_classdefs())
    parent_context = ModuleValue(
        inference_state, module,
        code_lines=parso.split_lines(code, keepends=True),
    ).as_context()

    return ValueSet([ClassValue(inference_state, parent_context, generated_class)])

def extract(script, new_name):
    """ The `args` / `kwargs` params are the same as in `api.Script`.
    :param operation: The refactoring operation to execute.
    :type operation: str
    :type source: str
    :return: list of changed lines/changed files
    """
    new_lines = split_lines(python_bytes_to_unicode(script.source))
    old_lines = new_lines[:]

    user_stmt = script._parser.user_stmt()

    # TODO care for multiline extracts
    dct = {}
    if user_stmt:
        pos = script._pos
        line_index = pos[0] - 1
        arr, index = helpers.array_for_pos(user_stmt, pos)
        if arr is not None:
            start_pos = arr[index].start_pos
            end_pos = arr[index].end_pos

            # take full line if the start line is different from end line
            e = end_pos[1] if end_pos[0] == start_pos[0] else None

code = base.format(
        typename=name,
        field_names=tuple(fields),
        num_fields=len(fields),
        arg_list=repr(tuple(fields)).replace("u'", "").replace("'", "")[1:-1],
        repr_fmt=', '.join(get_var(u'_repr_template').format(name=name) for name in fields),
        field_defs='\n'.join(get_var(u'_field_template').format(index=index, name=name)
                             for index, name in enumerate(fields))
    )

    # Parse source code
    module = evaluator.grammar.parse(code)
    generated_class = next(module.iter_classdefs())
    parent_context = ModuleContext(
        evaluator, module, None,
        code_lines=parso.split_lines(code, keepends=True),
    )
    return ContextSet(ClassContext(evaluator, parent_context, generated_class))

project._sys_path = sys_path
        self._inference_state = InferenceState(
            project, environment=environment, script_path=self.path
        )
        debug.speed('init')
        self._module_node, source = self._inference_state.parse_and_get_code(
            code=source,
            path=self.path,
            encoding=encoding,
            use_latest_grammar=path and path.endswith('.pyi'),
            cache=False,  # No disk cache, because the current script often changes.
            diff_cache=settings.fast_parser,
            cache_path=settings.cache_directory,
        )
        debug.speed('parsed')
        self._code_lines = parso.split_lines(source, keepends=True)
        self._code = source
        self._pos = line, column

        cache.clear_time_caches()
        debug.reset_time()