class_docstr: ### Shift right operation
  
  This shifts the sequence to the right by the given number of steps
docstr: * `x` is a tensor of shape `[seq_len, ...]`
code: def forward(self, x: torch.Tensor):
      """
      * `x` is a tensor of shape `[seq_len, ...]`
      """
      # If the shift is $0$ return the original
      if self.shift == 0:
          return x
      # Zeros to be appended to the left
      prefix = x.new_zeros([self.shift, *x.shape[1:]])
      # Concatenate the zeros and truncate the right
      return torch.cat([prefix, x[: -self.shift]])
  
imports: from typing import List
  import torch
  from torch import nn
  from labml_helpers.module import Module
  from labml_nn.transformers import MultiHeadAttention, TransformerLayer
  from labml_nn.transformers.feed_forward import FeedForward
  from labml_nn.transformers.utils import subsequent_mask
label_desc: Use image node_id 2 for calling the ShiftRight obj's underlying member method code with example usage: obj.forward(x) and returns: torch, x