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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 start(self):
 """ Invokes the mod-host process. mod-host requires JACK to be running. mod-host does not startup JACK automatically, so you need to start it before running mod-host. .. note:: This function is experimental. There is no guarantee that the process will actually be initiated. """

        if self.address != 'localhost':
            raise ModHostError('The host configured in the constructor isn''t "localhost". '
                               'It is not possible to start a process on another device.')

        try:
            subprocess.call([self.process, '-p', str(self.port)])

        except FileNotFoundError as e:
            exception = ModHostError(
                'mod-host not found. Did you install it? '
                '(https://github.com/moddevices/mod-host#building)'
            )

            raise exception from e

        self._started_with_this_api = True