code: def lognormal(
      x: TensorType, mu: TensorType, var: TensorType
  ) -> tf.Tensor:
      lnx = tf.math.log(x)
      return gaussian(lnx, mu, var) - lnx
  
file_path: GPflow/gpflow/logdensities.py
imports: import numpy
  import tensorflow
  from check_shapes import check_shapes
  from .base import TensorType
  from .utilities import to_default_float
label_desc: Use image node_id 2 for calling a global function with example usage: lognormal(x, mu, var) and returns: unknown