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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 send_signal(self, s):
 """ Send a signal to the daemon process. The signal must have been enabled using the ``signals`` parameter of :py:meth:`Service.__init__`. Otherwise, a ``ValueError`` is raised. """

        self._get_signal_event(s)  # Check if signal has been enabled
        pid = self.get_pid()
        if not pid:
            raise ValueError('Daemon is not running.')
        os.kill(pid, s)