code: def add_layer_timing_signal_sinusoid_1d(x, layer, num_layers):
    
  
    channels = common_layers.shape_list(x)[-1]
    signal = get_layer_timing_signal_sinusoid_1d(channels, layer, num_layers)
  
    return x + signal
docs: Add sinusoids of different frequencies as layer (vertical) timing signal.
  
    Args:
      x: a Tensor with shape [batch, length, channels]
      layer: layer num
      num_layers: total number of layers
  
    Returns:
      a Tensor the same shape as x.