code: def metric_matrix_test_data(self):
      data = [
          dict(
              base_point=None,
              expected=gs.array([[-1.0, 0.0], [0.0, 1.0]]),
          )
      ]
      return self.generate_tests(data)
  
file_path: geomstats/tests/tests_geomstats/test_geometry/data/minkowski.py
imports: import math
  import geomstats.backend
  from geomstats.test.data import TestData
  from .riemannian_metric import RiemannianMetricTestData
label_desc: Use image node_id 1 for calling the Minkowski2MetricTestData obj's underlying member method code with example usage: obj.metric_matrix_test_data() and returns: self