code: def embed_coords(self, coords):
      # Fill up a triangular matrix and then copy it to the other side.
      matrices = linalg.fill_triangular(coords)
      matrices = tf.linalg.matrix_transpose(matrices) + matrices
      matrices = tf.linalg.set_diag(
          matrices, tf.linalg.diag_part(matrices) / 2.0
      )
      return matrices
  
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.bijectors import exp
  from tensorflow_probability.python.bijectors import reshape
  from tensorflow_probability.python.bijectors import scale
  from tensorflow_probability.python.experimental.tangent_spaces import spaces_test_util
  from tensorflow_probability.python.experimental.tangent_spaces import symmetric_matrix
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import linalg
label_desc: Use image node_id 2 for calling the _SymmetricMatrixTest obj's underlying member method code with example usage: obj.embed_coords(coords) and returns: matrices