code: def exp_test_data(self):
      tangent_vec = gs.array(
          [
              [[gs.pi / 2, 0, 0], [0, 0, 0]],
              [[0, -gs.pi / 2, 0], [0, 0, 0]],
          ]
      )
      expected = gs.array([self.pu1, self.pu0])
  
      data = [
          dict(
              tangent_vec=tangent_vec,
              base_point=gs.array([self.pu0, self.pu1]),
              expected=expected,
          )
      ]
  
      return self.generate_tests(data)
  
imports: import geomstats.backend
  from geomstats.test.data import TestData
label_desc: Use image node_id 2 for calling the SasakiMetricSphereTestData obj's underlying member method code with example usage: obj.exp_test_data() and returns: self