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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 on_sigchld(self, _signum, _unused_frame):
 """Invoked when a child sends up an SIGCHLD signal. :param int _signum: The signal that was invoked :param frame _unused_frame: The frame that was interrupted """

        LOGGER.info('SIGCHLD received from child')
        if not self.active_processes(False):
            LOGGER.info('Stopping with no active processes and child error')
            signal.setitimer(signal.ITIMER_REAL, 0, 0)
            self.set_state(self.STATE_STOPPED)