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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _reflow_lines(parsed_tokens, indentation, max_line_length, start_on_prefix_line):
 """Reflow the lines so that it looks nice."""


    if unicode(parsed_tokens[0]) == 'def':
        # A function definition gets indented a bit more.
        continued_indent = indentation + ' ' * 2 * DEFAULT_INDENT_SIZE
    else:
        continued_indent = indentation + ' ' * DEFAULT_INDENT_SIZE

    break_after_open_bracket = not start_on_prefix_line

    lines = ReformattedLines(max_line_length)
    lines.add_indent(len(indentation.lstrip('\r\n')))

    if not start_on_prefix_line:
        # If splitting after the opening bracket will cause the first element
        # to be aligned weirdly, don't try it.
        first_token = get_item(parsed_tokens, 0)
        second_token = get_item(parsed_tokens, 1)

        if (
            first_token and second_token and
            unicode(second_token)[0] == '(' and
            len(indentation) + len(first_token) + 1 == len(continued_indent)
        ):
            return None

    for item in parsed_tokens:
        lines.add_space_if_needed(unicode(item), equal=True)

        save_continued_indent = continued_indent
        if start_on_prefix_line and isinstance(item, Container):
            start_on_prefix_line = False
            continued_indent = ' ' * (lines.current_size() + 1)

        item.reflow(lines, continued_indent, break_after_open_bracket)
        continued_indent = save_continued_indent

    return lines.emit()