code: def call(self, prev_layers):
      chosen_input, chosen_mask = self.input_choice(prev_layers)
      cell_out = self.op_choice(chosen_input)
      return cell_out, chosen_mask
  
imports: import tensorflow
  from tensorflow.keras import Model, Sequential
  from tensorflow.keras.layers import AveragePooling2D, BatchNormalization, Conv2D, Dense, Dropout, GlobalAveragePooling2D, MaxPool2D, ReLU, SeparableConv2D
  from nni.nas.tensorflow.mutables import InputChoice, LayerChoice, MutableScope
label_desc: Use image node_id 2 for calling the Cell obj's underlying member method code with example usage: obj.call(prev_layers) and returns: cell_out,  chosen_mask