docs: def get_tree(ident_hash, baked=False):
      """Return a tree structure of the Collection"""
      id, version = get_id_n_version(ident_hash)
  
      stmt = _get_sql('get-tree.sql')
      args = dict(id=id, version=version, baked=baked)
  
      with db_connect() as db_conn:
          with db_conn.cursor() as cursor:
              cursor.execute(stmt, args)
              try:
                  tree = cursor.fetchone()[0]
              except TypeError:
                  raise NotFound(ident_hash)
      if tree is None:
          raise NotFound(ident_hash)
  
      return tree