code: def configure_optimizers(self):
      optimizer = torch.optim.Adam(self.parameters(), lr=1e-2)
      return optimizer
  
file_path: pytorch_geometric_temporal/examples/recurrent/lightning_example.py
imports: import torch
  from torch.nn import functional
  import pytorch_lightning
  from pytorch_lightning.callbacks.early_stopping import EarlyStopping
  from torch_geometric_temporal.nn.recurrent import DCRNN
  from torch_geometric_temporal.dataset import ChickenpoxDatasetLoader
  from torch_geometric_temporal.signal import temporal_signal_split
label_desc: Use image node_id 2 for calling the LitDiffConvModel obj's underlying member method code with example usage: obj.configure_optimizers() and returns: optimizer