class_docstr: Test np <---> json
code: def test_unsupport(self):
      arr = np.random.rand(2, 4, 4)
      arr = arr.astype(np.float128)
      with self.assertRaises(ValueError):
          to_json(arr)
  
imports: import unittest
  import numpy
  from towhee.utils.serializer import to_json, from_json
label_desc: Use image node_id 2 for calling the TestNPFormat obj's underlying member method code with example usage: obj.test_unsupport() without return types