Converts a dictionary of string->int to a tf.Example.

def dict_to_example(dictionary):
  """Converts a dictionary of string->int to a tf.Example."""
  features = {}
  for k, v in six.iteritems(dictionary):
    features[k] = tf.train.Feature(int64_list=tf.train.Int64List(value=v))
  return tf.train.Example(features=tf.train.Features(feature=features))