code: def encode_item(self, x):
      h = self.item_encoder(x)
      return self.item_mu(h), torch.sigmoid(self.item_std(h))
  
file_path: cornac/cornac/models/bivaecf/bivae.py
imports: import itertools
  import numpy
  import torch
  import torch.nn
  from tqdm.auto import trange
label_desc: Use image node_id 6 for calling the BiVAE obj's underlying member method code with example usage: obj.encode_item(x) and returns: self,  torch