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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 refresh(self):
 """ Fetches all current container names from the client, along with their id. """

        if not self._client:
            return
        current_containers = self._client.containers(all=True)
        self.clear()
        for container in current_containers:
            container_names = container.get('Names')
            if container_names:
                c_id = container['Id']
                self.update((name[1:], c_id)
                            for name in container_names)