if pdh not in self.collections:
logger.debug("Creating collection reader for %s", pdh)
cr = arvados.collection.CollectionReader(pdh, api_client=self.api_client,
if pdh not in self.collections:
logger.debug("Creating collection reader for %s", pdh)
cr = arvados.collection.CollectionReader(pdh, api_client=self.api_client,