code: func (c *coordinator) accessPolicyForCollection(chdr *common.ChannelHeader, namespace string, col string) (privdata.CollectionAccessPolicy, error) {
  	cp := common.CollectionCriteria{
  		Channel:    chdr.ChannelId,
  		Namespace:  namespace,
  		Collection: col,
  		TxId:       chdr.TxId,
  	}
  	sp, err := c.CollectionStore.RetrieveCollectionAccessPolicy(cp)
  
  	if _, isNoSuchCollectionError := err.(privdata.NoSuchCollectionError); err != nil && !isNoSuchCollectionError {
  		logger.Warning("Failed obtaining policy for", cp, "due to database unavailability:", err)
  		return nil, err
  	}
  	return sp, nil
  }
docs: // accessPolicyForCollection retrieves a CollectionAccessPolicy for a given namespace, collection name
  // that corresponds to a given ChannelHeader