'Transform the inputs.
Args:
xs: A list of num_datashards Tensors (one per shard)
each with shape [batch, p0, p1, depth]
data_parallelism: a expert_utils.Parallelism object
Returns:
shaded_body_input: A list of num_datashards Tensors, each with shape
[batch, p0, p1, body_input_depth].'

def bottom_sharded(self, xs, data_parallelism):

    return data_parallelism(self.bottom, xs)
