message: Fix tf.keras.optimizers.SGD Nesterov momentum doc
diff: @@ -43,7 +43,7 @@ class SGD(optimizer_v2.OptimizerV2):
  w = w + velocity
  ```
  - When `nesterov=False`, this rule becomes:
  + When `nesterov=True`, this rule becomes:
  ```python
  velocity = momentum * velocity - learning_rate * g
  