code: def cos_sin(self, x: Tensor):
      return torch.cat([torch.cos(x), torch.sin(x)], -1)
  
imports: from typing import List, Optional
  import torch
  from torch import Tensor, nn
  from ..constants import CATEGORICAL, FEATURES, LABEL, LOGITS, NUMERICAL
  from .custom_transformer import CLSToken, Custom_Transformer, _TokenInitialization
  from .utils import init_weights
label_desc: Use image node_id 2 for calling the Periodic obj's underlying member method code with example usage: obj.cos_sin(x) and returns: torch