message: update tf.keras.Model.compile docstring
diff: @@ -241,10 +241,12 @@ class Model(network.Network):
  optimizer: String (name of optimizer) or optimizer instance.
  See `tf.keras.optimizers`.
  loss: String (name of objective function), objective function or
  - `tf.losses.Loss` instance. See `tf.losses`. If the model has
  - multiple outputs, you can use a different loss on each output by
  - passing a dictionary or a list of losses. The loss value that will
  - be minimized by the model will then be the sum of all individual
  + `tf.keras.losses.Loss` instance. See `tf.keras.losses`. An objective
  + function is any callable with the signature
  + `scalar_loss = fn(y_true, y_pred)`. If the model has multiple
  + outputs, you can use a different loss on each output by passing a
  + dictionary or a list of losses. The loss value that will be
  + minimized by the model will then be the sum of all individual
  losses.
  metrics: List of metrics to be evaluated by the model during training
  and testing. Typically you will use `metrics=['accuracy']`.
  