docs: def make_object_graph(obj, fpath='sample_graph.png'):
      """ memoryprofile with objgraph
  
      Examples:
          #import objgraph
          #objgraph.show_most_common_types()
          #objgraph.show_growth()
          #memtrack.report()
          #memtrack.report()
          #objgraph.show_growth()
          #import gc
          #gc.collect()
          #memtrack.report()
          #y = 0
          #objgraph.show_growth()
          #memtrack.report()
          #utool.embed()
  
      References:
          http://mg.pov.lt/objgraph/
      """
      import objgraph
      objgraph.show_most_common_types()
      #print(objgraph.by_type('ndarray'))
      #objgraph.find_backref_chain(
      #     random.choice(objgraph.by_type('ndarray')),
      #     objgraph.is_proper_module)
      objgraph.show_refs([obj], filename='ref_graph.png')
      objgraph.show_backrefs([obj], filename='backref_graph.png')