code: def test_getitem_v2(self):
      x = np.random.rand(10, 5)
      fa = FieldArray("my_field", x)
      indices = [0, 1, 3, 4, 6]
      for a, b in zip(fa[indices], x[indices]):
          assert a.tolist() == b.tolist()
  
imports: import os
  import pytest
  import numpy
  from fastNLP.core.dataset import DataSet, FieldArray, Instance, ApplyResultException
  from fastNLP import logger
label_desc: Use image node_id 3 for calling the TestFieldArray obj's underlying member method code with example usage: obj.test_getitem_v2() without return types