code: def test_empty_input_of_high_rank(self):
      pb = self.histogram("empty_but_fancy", [[[], []], [[], []]])
      buckets = tensor_util.make_ndarray(pb.value[0].tensor)
      # By default there will be 30 buckets.
      np.testing.assert_allclose(buckets, np.zeros((30, 3)))
  
imports: import glob
  import os
  import numpy
  import tensorflow
  from tensorboard.compat import tf2
  from tensorboard.compat.proto import summary_pb2
  from tensorboard.plugins.histogram import metadata
  from tensorboard.plugins.histogram import summary
  from tensorboard.util import tensor_util
label_desc: Use image node_id 13 for calling the SummaryV3OpTest obj's underlying member method code with example usage: obj.test_empty_input_of_high_rank() without return types