Make anitools python2 friendly

# Written by Roman Zubatyuk and Justin S. Smith

# Modified by Yutong Zhao to make python2 compatible

import h5py

import numpy as np

import platform

        yield data

      else:  # test for group (go down)

        yield from self.h5py_dataset_iterator(item, path)

        for s in self.h5py_dataset_iterator(item, path):

          yield s

  ''' Default class iterator (iterate through all data) '''