code: def check_tree(tree, tree_number, tree_class=None):
      assert tree is not None
      assert len(tree) > 0
      assert tree._tree_number == tree_number
      assert tree._tree_class == tree_class
  
      assert tree.root_node is not None
      assert tree.left_children is not None
      assert tree.right_children is not None
      assert tree.thresholds is not None
      assert tree.nas is not None
      assert tree.descriptions is not None
      assert tree.node_ids is not None
      assert tree.model_id is not None
      assert tree.levels is not None
      assert tree.root_node.na_direction is not None
      assert tree.root_node.id is not None
  
imports: import h2o
  from h2o.tree import H2OTree
  from h2o.estimators import H2OIsolationForestEstimator
  from tests import pyunit_utils
label_desc: Use image node_id 1 for calling a global function with example usage: check_tree(tree, tree_number, tree_class) without return types