<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def filter(self, filter_func, reverse=False):
 """Filter current log lines by a given filter function. This allows to drill down data out of the log file by filtering the relevant log lines to analyze. For example, filter by a given IP so only log lines for that IP are :param filter_func: [required] Filter method, see filters.py for all available filters. :type filter_func: function :param reverse: negate the filter (so accept all log lines that return ``False``). :type reverse: boolean :returns: a new instance of Log containing only log lines that passed the filter function. :rtype: :class:`Log` """

        new_log_file = Log()
        new_log_file.logfile = self.logfile

        new_log_file.total_lines = 0

        new_log_file._valid_lines = []
        new_log_file._invalid_lines = self._invalid_lines[:]

        # add the reverse conditional outside the loop to keep the loop as
        # straightforward as possible
        if not reverse:
            for i in self._valid_lines:
                if filter_func(i):
                    new_log_file.total_lines += 1
                    new_log_file._valid_lines.append(i)
        else:
            for i in self._valid_lines:
                if not filter_func(i):
                    new_log_file.total_lines += 1
                    new_log_file._valid_lines.append(i)

        return new_log_file