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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):
 """ Start a container by starting all of its extensions. """

        _log.debug('starting %s', self)
        self.started = True

        with _log_time('started %s', self):
            self.extensions.all.setup()
            self.extensions.all.start()