def METHOD_NAME(x, block_size):
  """Inverse of `time_to_batch(x, block_size)`.
  Args:
    x: Tensor of shape [nb*block_size, k, n] for some natural number k.
    block_size: number of time steps (i.e. size of dimension 1) in the output
      tensor.
  Returns:
    Tensor of shape [nb, k*block_size, n].
  """
  shape = x.get_shape().as_list()
  y = tf.reshape(x, [shape[0] // block_size, block_size, shape[1], shape[2]])
  y = tf.transpose(y, [0, 2, 1, 3])
  y = tf.reshape(y, [shape[0] // block_size, shape[1] * block_size, shape[2]])
  y.set_shape([mul_or_none(shape[0], 1. / block_size),
               mul_or_none(shape[1], block_size),
               shape[2]])
  return y