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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 close(self):
 """ Remove the audio plugins loaded and closes connection with mod-host. .. note:: If the mod-host process has been created with :meth:`~pluginsmanager.observer.mod_host.ModHost.start()` method, it will be finished. """

        if self.host is None:
            raise ModHostError('There is no established connection with mod-host. '
                               'Did you call the `connect()` method?')

        super(ModHost, self).close()

        if self._started_with_this_api:
            self.host.quit()
        else:
            self.host.close()