code: def num_inputs(self):
      return len(self.input_sizes)
  
imports: import math
  from typing import Dict, List, Tuple, Union
  import torch
  import torch.nn
  import torch.nn.functional
label_desc: Use image node_id 3 for calling the VariableSelectionNetwork obj's underlying member method code with example usage: obj.num_inputs() and returns: len