class_docstr: Gate tests.
class_docstr_tok: ["Gate","tests","."]
code: def test_identity(self, inp_state, tol):
      inp_cov_mat = inp_state[0]
      inp_means = inp_state[1]
  
      O = qml.Identity.identity_op()
      out_means = O @ inp_means
      out_cov_mat = O @ inp_cov_mat @ O.T
  
      assert np.allclose(out_means, inp_means, atol=tol)
      assert np.allclose(out_cov_mat, inp_cov_mat, atol=tol)
  
imports: import numpy
  import numpy.random
  import pytest
  from scipy.linalg import block_diag
  from scipy.special import factorial
  import pennylane
  from pennylane import DeviceError
  from pennylane.devices.default_gaussian import fock_prob, rotation, squeezing, quadratic_phase, beamsplitter, two_mode_squeezing, controlled_addition, controlled_phase, vacuum_state, coherent_state, squeezed_state, displaced_squeezed_state, thermal_state
  from pennylane.wires import Wires
label_desc: Use image node_id 1 for calling the TestGates obj's underlying member method code with example usage: obj.test_identity(inp_state, tol) without return types