class_docstr: loss util unittest
code: def setUp(self):
      super().setUp()
      """ setup """
      # classfication: shape [2, 6]
      self.logits = np.array(
          [[10, 23, 43, 23, 12, 23], [32, 10, 23, 45, 23, 0]],
          dtype=np.float32,
      )
      self.labels = np.array([2, 3], dtype=np.int32)
      # seq2seq: shape [2, 3, 6]
      self.seq_logits = np.array(
          [
              [
                  [10, 2, 11, 23, 12, 42],
                  [12, 32, 11, 2, 0, 0],
                  [12, 32, 11, 2, 0, 0],
              ],
              [
                  [3, 11, 2, 32, 4, 8],
                  [12, 1, 32, 0, 0, 0],
                  [0, 0, 0, 0, 0, 0],
              ],
          ],
          dtype=np.float32,
      )
      self.seq_labels = np.array([[5, 1, 1], [3, 2, 0]], dtype=np.int32)
      self.input_length = np.array([[3, 2]], dtype=np.int32)
      self.label_length = np.array([3, 2], dtype=np.int32)
      # test misclassified examples
      self.logits_2 = np.array(
          [[10, 2, 3, 4, 5, 6], [2, 3, 10, 4, 5, 1]], dtype=np.float32
      )
  
file_path: delta/delta/utils/loss/loss_utils_test.py
imports: import numpy
  import delta.compat
  from absl import logging
  from delta.utils.loss import loss_utils
label_desc: Use image node_id 1 for calling the LossUtilTest obj's underlying member method code with example usage: obj.setUp() without return types