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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 delete_all_volumes(self):
 """Remove all the volumes. Only the manager nodes can delete a volume """

        # Raise an exception if we are not a manager
        if not self._manager:
            raise RuntimeError('Volumes can only be deleted '
                               'on swarm manager nodes')

        volume_list = self.get_volume_list()
        for volumes in volume_list:
            # Remove all the services
            self._api_client.remove_volume(volumes, force=True)