code: def call(self, inputs):
      x, a, e = inputs
      x = self.masking(x)
      x = self.conv1([x, a, e])
      x = self.conv2([x, a, e])
      output = self.global_pool(x)
      output = self.dense(output)
  
      return output
  
file_path: spektral/examples/graph_prediction/qm9_ecc_batch.py
imports: import numpy
  from tensorflow.keras.layers import Dense
  from tensorflow.keras.models import Model
  from tensorflow.keras.optimizers import Adam
  from spektral.data import BatchLoader
  from spektral.datasets import QM9
  from spektral.layers import ECCConv, GlobalSumPool, GraphMasking
label_desc: Use image node_id 2 for calling the Net obj's underlying member method code with example usage: obj.call(inputs) and returns: output