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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 killall(self):
 """ Kill all children """

        for pid in set(self):
            try:
                os.kill(pid, signal.SIGTERM)
            except OSError, e: # pragma: nocover
                if e.errno == errno.ESRCH:
                    "Process previously died on its own"
            self.remove(pid)