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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 publish(self, distribution, storage=""):
 """ Get or create publish """

        try:
            return self._publishes[distribution]
        except KeyError:
            self._publishes[distribution] = Publish(self.client, distribution, timestamp=self.timestamp, storage=(storage or self.storage))
            return self._publishes[distribution]