code: def test_getitem(self, device, batch_size, cdtype):
      z = self._make_rand_data(device, cdtype, (batch_size,))
      s = So2(z)
      n = 1 if batch_size is None else batch_size
      for i in range(n):
          if batch_size is None:
              expected = s.z
              actual = z
          else:
              expected = s[i].z.data.squeeze()
              actual = z[i]
          self.assert_close(expected, actual)
  
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 10 for calling the TestSo2 obj's underlying member method code with example usage: obj.test_getitem(device, batch_size, cdtype) without return types