code: def test_model(self):
      a = torch.rand(2, 2)
      b = torch.rand(1, 2)
      out = krylov(l=2, a=a, b=b)
      self.assertEqual(out.shape, (1, 2, 2))
  
imports: import unittest
  import torch
  from towhee.models.vis4mer.utils import krylov
label_desc: Use image node_id 1 for calling the KrylovTest obj's underlying member method code with example usage: obj.test_model() without return types