class_docstr: Bijector that computes `Y = tanh(X)`, therefore `Y in (-1, 1)`.
  
  This can be achieved by an affine transform of the Sigmoid bijector, i.e.,
  it is equivalent to
  ```
  tfb.Chain([tfb.Shift(shift=-1.),
             tfb.Scale(scale=2.),
             tfb.Sigmoid(),
             tfb.Scale(scale=2.)])
  ```
  
  However, using the `Tanh` bijector directly is slightly faster and more
  numerically stable.
code: def _forward(self, x):
      return tf.math.tanh(x)
  
file_path: probability/tensorflow_probability/python/bijectors/tanh.py
imports: import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.bijectors import bijector
label_desc: Use image node_id 4 for calling the Tanh obj's underlying member method code with example usage: obj._forward(x) and returns: tf