code: def forward(self, x):
      a = self.mlp(x)
      return a[:, 0 : self.z_size], softplus(a[:, self.z_size :])
  
imports: import torch
  import torch.nn
  from torch.nn.functional import softplus
label_desc: Use image node_id 2 for calling the Encoder obj's underlying member method code with example usage: obj.forward(x) and returns: a,  softplus