code: def test_dense_to_sparse_2d(self):
      st = sparse.dense_to_sparse([[1, 2, 0, 0], [3, 4, 5, 0]])
      result = self.evaluate(st)
      self.assertAllEqual(
          [[0, 0], [0, 1], [1, 0], [1, 1], [1, 2]], result.indices
      )
      self.assertAllEqual([1, 2, 3, 4, 5], result.values)
      self.assertAllEqual([2, 4], result.dense_shape)
  
file_path: probability/tensorflow_probability/python/math/sparse_test.py
imports: import numpy
  import tensorflow.compat.v1
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import sparse
label_desc: Use image node_id 6 for calling the SparseTest obj's underlying member method code with example usage: obj.test_dense_to_sparse_2d() without return types