code: def test_hat(self, device, dtype, batch_size):
      v = torch.tensor([1, 2, 3], device=device, dtype=dtype)
      expected = v
      if batch_size is not None:
          v = v.repeat(batch_size, 1)
      hat = So3.hat(v)
      if batch_size is None:
          hat = hat[None]
      self.assert_close(hat.unique()[-3:], expected)
  
imports: import pytest
  import torch
  from kornia.geometry.conversions import euler_from_quaternion
  from kornia.geometry.liegroup import So3
  from kornia.geometry.quaternion import Quaternion
  from kornia.geometry.vector import Vector3
  from kornia.testing import BaseTester
label_desc: Use image node_id 16 for calling the TestSo3 obj's underlying member method code with example usage: obj.test_hat(device, dtype, batch_size) without return types