code: def test_numpy_I(matrices, backend_fw):
      data, data_gt = matrices
      assume(
          np.linalg.cond(data.A.data) < 1 / sys.float_info.epsilon
          and data.shape[0] == data.shape[1]
      )
      ret = ivy_np.ravel(data.I)
      ret_gt = np.ravel(data_gt.I)
      helpers.value_test(
          ret_np_flat=ret,
          ret_np_from_gt_flat=ret_gt,
          backend=backend_fw,
          ground_truth_backend="numpy",
      )
  
imports: from hypothesis import assume, strategies
  import numpy
  import sys
  import ivy
  import ivy_tests.test_ivy.helpers
  from ivy_tests.test_ivy.helpers import handle_frontend_method, handle_frontend_test
  import ivy.functional.frontends.numpy
label_desc: Use image node_id 6 for calling a global function with example usage: test_numpy_I(matrices, backend_fw) without return types