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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 parse_thread(self, participants, element_iter, require_flush):
 """ Parses a thread with appropriate CLI feedback. :param participants: The participants in this thread. :param element_iter: The XML iterator to parse the data from. :param require_flush: Whether the iterator needs to be flushed if it is determined that the thread should be skipped. :return: A `ChatThread` object if not skipped, otherwise `None`. """


        # Very rarely threads may lack information on who the
        # participants are. We will consider those threads corrupted
        # and skip them.
        participants_text = _truncate(', '.join(participants), 60)
        if participants:
            skip_thread = not self.should_record_thread(participants)
            participants_text = yellow("[%s]" % participants_text)
        else:
            participants_text = "unknown participants"
            skip_thread = True
        if skip_thread:
            line = "\rSkipping chat thread with %s..." % \
                   yellow(participants_text)
        else:
            participants_key = ", ".join(participants)
            if participants_key in self.chat_threads:
                thread_current_len = len(self.chat_threads[participants_key])
                line = "\rContinuing chat thread with %s %s..." \
                       % (yellow(participants_text), magenta("<@%d messages>" % thread_current_len))
            else:
                line = "\rDiscovered chat thread with %s..." \
                       % yellow(participants_text)
        if self.progress_output:
            sys.stderr.write(line.ljust(self.last_line_len))
            sys.stderr.flush()
        self.last_line_len = len(line)

        parser = ChatThreadParser(
            element_iter, self.timezone_hints, self.use_utc, self.name_resolver,
            self.no_sender_warning, self.seq_num)

        if skip_thread:
            if require_flush:
                parser.skip()
        else:
            self.no_sender_warning, thread = parser.parse(participants)
            return thread