message: Modified the Example code such that it is executable
  Github Gist for working code is
  Fixes
diff: @@ -51,24 +51,35 @@ class SequenceFeatures(kfc._BaseFeaturesLayer):
  Example:
  ```python
  +
  + import tensorflow as tf
  +
  # Behavior of some cells or feature columns may depend on whether we are in
  # training or inference mode, e.g. applying dropout.
  training = True
  - rating = sequence_numeric_column('rating')
  - watches = sequence_categorical_column_with_identity(
  + rating = tf.feature_column.sequence_numeric_column('rating')
  + watches = tf.feature_column.sequence_categorical_column_with_identity(
  'watches', num_buckets=1000)
  - watches_embedding = embedding_column(watches, dimension=10)
  + watches_embedding = tf.feature_column.embedding_column(watches,
  + dimension=10)
  columns = [rating, watches_embedding]
  - sequence_input_layer = SequenceFeatures(columns)
  - features = tf.io.parse_example(...,
  - features=make_parse_example_spec(columns))
  + features = {
  + 'rating': tf.sparse.from_dense([[1.0,1.1, 0, 0, 0],
  + [2.0,2.1,2.2, 2.3, 2.5]]),
  + 'watches': tf.sparse.from_dense([[2, 85, 0, 0, 0],[33,78, 2, 73, 1]])
  + }
  +
  + sequence_input_layer = tf.keras.experimental.SequenceFeatures(columns)
  sequence_input, sequence_length = sequence_input_layer(
  features, training=training)
  +
  sequence_length_mask = tf.sequence_mask(sequence_length)
  - rnn_cell = tf.keras.layers.SimpleRNNCell(hidden_size, training=training)
  - rnn_layer = tf.keras.layers.RNN(rnn_cell, training=training)
  + hidden_size = 32
  +
  + rnn_cell = tf.keras.layers.SimpleRNNCell(hidden_size)
  + rnn_layer = tf.keras.layers.RNN(rnn_cell)
  outputs, state = rnn_layer(sequence_input, mask=sequence_length_mask)
  ```
  """
  