code: def test_CovIdentity(seeded_rng):
      cov = CovIdentity(size=m)
  
      # compute the naive version
      cov_np = np.eye(m)
      logdet_np, sinv_np, sinvx_np = logdet_sinv_np(X, cov_np)
      assert_allclose(logdet_np, cov.logdet, rtol=rtol)
      assert_allclose(sinv_np, cov.solve(eye), rtol=rtol)
      assert_allclose(sinvx_np, cov.solve(X_tf), rtol=rtol)
  
imports: import pytest
  import numpy
  from numpy.testing import assert_allclose
  from scipy.stats import norm, wishart, invgamma, invwishart
  import tensorflow
  from brainiak.matnormal.covs import CovIdentity, CovAR1, CovIsotropic, CovDiagonal, CovDiagonalGammaPrior, CovUnconstrainedCholesky, CovUnconstrainedCholeskyWishartReg, CovUnconstrainedInvCholesky, CovKroneckerFactored
label_desc: Use image node_id 4 for calling a global function with example usage: test_CovIdentity(seeded_rng) without return types