code: def l1_distance(prediction, ground_truth):
      """Average L1 distance difference between two 1-D vectors."""
      prediction, ground_truth = np.squeeze(prediction), np.squeeze(
          ground_truth
      )
      min_length = min(prediction.size, ground_truth.size)
      diff = prediction[:min_length] - ground_truth[:min_length]
      return np.abs(diff)
  
imports: import dataclasses
  from absl import logging
  import ddsp
  import librosa
  import mir_eval
  import note_seq
  from note_seq import sequences_lib
  import numpy
  import tensorflow.compat.v2
label_desc: Use image node_id 2 for calling a global function with example usage: l1_distance(prediction, ground_truth) and returns: np