code: def test_forest():
      """test creation of forest object"""
      F = simple_forest()
      assert F.E == 8
      assert F.cc().max() == 0
  
file_path: nipy/nipy/algorithms/graph/tests/test_forest.py
imports: import numpy
  from ..forest import Forest
label_desc: Use image node_id 2 for calling a global function with example usage: test_forest() without return types