old_contents: from treestore import Treestore
  import settings
  
  
  def get_treestore():
      return Treestore(**settings.TREESTORE_KWARGS)
  
  def uri_from_tree_id(tree_id):
      return (settings.TREE_URI + tree_id)
  
  def tree_id_from_uri(uri):
      if uri.startswith(settings.TREE_URI):
          uri = uri.replace(settings.TREE_URI, '', 1)
      return uri
new_contents: from treestore import Treestore
  import settings
  
  
  def get_treestore():
      return Treestore(**settings.TREESTORE_KWARGS)
  
  def uri_from_tree_id(tree_id):
      return Treestore.uri_from_id(tree_id, base_uri=settings.TREE_URI)
  
  def tree_id_from_uri(uri):
      if uri.startswith(settings.TREE_URI):
          uri = uri.replace(settings.TREE_URI, '', 1)
      if uri.endswith('/'): uri = uri.rstrip('/')
      return uri
subject: Use treestore to get URIs from IDs.