code: def get_batch(data_source, i, seq_len=None):
      
      seq_len = min(seq_len if seq_len else args.bptt, len(data_source) - 1 - i)
      data = data_source[i:i+seq_len]
      target = data_source[i+1:i+1+seq_len]
      return data, target
docs: Get mini-batches of the dataset.
  
      Parameters
      ----------
      data_source : NDArray
          The dataset is evaluated on.
      i : int
          The index of the batch, starting from 0.
      seq_len : int
          The length of each sample in the batch.
  
      Returns
      -------
      data: NDArray
          The context
      target: NDArray
          The words to predict