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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 stop(self):
 """ Stops the backend process. """

        if self._process is None:
            return
        if self._shared:
            BackendManager.SHARE_COUNT -= 1
            if BackendManager.SHARE_COUNT:
                return
        comm('stopping backend process')
        # close all sockets
        for s in self._sockets:
            s._callback = None
            s.close()

        self._sockets[:] = []
        # prevent crash logs from being written if we are busy killing
        # the process
        self._process._prevent_logs = True
        while self._process.state() != self._process.NotRunning:
            self._process.waitForFinished(1)
            if sys.platform == 'win32':
                # Console applications on Windows that do not run an event
                # loop, or whose event loop does not handle the WM_CLOSE
                # message, can only be terminated by calling kill().
                self._process.kill()
            else:
                self._process.terminate()
        self._process._prevent_logs = False
        self._heartbeat_timer.stop()
        comm('backend process terminated')