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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 watch_logfile(self, logfile_path):
 """Analyzes queries from the tail of a given log file"""

        self._run_stats['logSource'] = logfile_path
        log_parser = LogParser()

        # For each new line in the logfile ...
        output_time = time.time() + WATCH_DISPLAY_REFRESH_SECONDS
        try:
            firstLine = True
            for line in self._tail_file(open(logfile_path),
                                        WATCH_INTERVAL_SECONDS):
                if firstLine:
                    self._run_stats['timeRange']['start'] = get_line_time(line)
                self._process_query(line, log_parser)
                self._run_stats['timeRange']['end'] = get_line_time(line)
                if time.time() >= output_time:
                    self._output_aggregated_report(sys.stderr)
                    output_time = time.time() + WATCH_DISPLAY_REFRESH_SECONDS
        except KeyboardInterrupt:
            sys.stderr.write("Interrupt received\n")
        finally:
            self._output_aggregated_report(sys.stdout)

        return 0