docstr: Batch matrix multiplication test.
docstr_tok: ["Batch","matrix","multiplication","test","."]
code: def test_matmul(self):
      """Batch matrix multiplication test."""
  
      np.random.seed(42)
  
      a = _random_sparse_tensor([200, 2, 2])
      b = _random_sparse_tensor([200, 2, 2])
      u = tf.math.log(tf.matmul(a, b))
      v = _binary_einslogsumexp(
          "hij,hjk->hik", tf.math.log(a), tf.math.log(b)
      )
  
      self.assertAllClose(u, v)
  
imports: import hypothesis
  from hypothesis.extra import numpy
  import hypothesis.strategies
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.experimental.marginalize.logeinsumexp import _binary_einslogsumexp
  from tensorflow_probability.python.experimental.marginalize.logeinsumexp import logeinsumexp
  from tensorflow_probability.python.internal import test_util
  import tensorflow_probability.python.internal.hypothesis_testlib
label_desc: Use image node_id 8 for calling the _EinLogSumExpTest obj's underlying member method code with example usage: obj.test_matmul() without return types