code: def test_hat(self, device, dtype, batch_size):
      theta = self._make_rand_data(device, dtype, (batch_size,))
      m = So2.hat(theta)
      o = torch.ones((2, 1), device=device, dtype=dtype)
      self.assert_close(
          (m @ o).reshape(-1, 2, 1),
          theta.reshape(-1, 1, 1).repeat(1, 2, 1),
      )
  
imports: import pytest
  import torch
  from kornia.geometry.liegroup import So2
  from kornia.geometry.vector import Vector2
  from kornia.testing import BaseTester
label_desc: Use image node_id 16 for calling the TestSo2 obj's underlying member method code with example usage: obj.test_hat(device, dtype, batch_size) without return types