code: def log_gaussian_pdf(x, mu, sigma):  # pylint: disable=invalid-name
      """Returns `log N(x | mu, sigma)`.
  
      Args:
        x: <tbd>
        mu: <tbd>
        sigma: <tbd>
      """
      a = mu.shape[-1] * jnp.log(2 * jnp.pi)
      _, b = jnp.linalg.slogdet(sigma)
      y = jnp.linalg.solve(sigma, x - mu)
      y = jnp.expand_dims(y, axis=-1)
      xm = jnp.expand_dims(x - mu, axis=-2)
      c = jnp.matmul(xm, y)
      c = jnp.squeeze(jnp.squeeze(c, axis=-1), axis=-1)
      return -0.5 * (a + b + c)
  
imports: from absl import logging
  import numpy
  import tensorflow
  from trax import fastmath
  from trax.fastmath import numpy
  from trax.layers import base
  from trax.layers import initializers
  from trax.layers.assert_shape import assert_shape
  from trax.layers.base import Fn
label_desc: Use image node_id 17 for calling a global function with example usage: log_gaussian_pdf(x, mu, sigma) and returns: unknown