code: def expected_results(self, phi):
      density_i = np.array(
          [[np.cos(phi / 2) ** 2, 0], [0, np.sin(phi / 2) ** 2]]
      )
      density_both = np.array(
          [
              [np.cos(phi / 2) ** 2, 0, 0, 0.0 + np.sin(phi) * 0.5j],
              [0, 0, 0, 0],
              [0, 0, 0, 0],
              [0.0 - np.sin(phi) * 0.5j, 0, 0, np.sin(phi / 2) ** 2],
          ]
      )
      eig_1 = (
          1
          + np.sqrt(1 - 4 * np.cos(phi / 2) ** 2 * np.sin(phi / 2) ** 2)
      ) / 2
      eig_2 = (
          1
          - np.sqrt(1 - 4 * np.cos(phi / 2) ** 2 * np.sin(phi / 2) ** 2)
      ) / 2
      eigs = [eig_1, eig_2]
      eigs = [eig for eig in eigs if eig > 0]
      rho_log_rho = eigs * np.log(eigs)
      expected_entropy = -np.sum(rho_log_rho)
      mutual_info = 2 * expected_entropy
  
      return (
          density_i,
          density_i,
          density_both,
          expected_entropy,
          expected_entropy,
          mutual_info,
      )
  
imports: import pytest
  import numpy
  import pennylane
  from pennylane.devices.qubit import simulate, get_final_state, measure_final_state
label_desc: Use image node_id 1 for calling the TestQInfoMeasurements obj's underlying member method code with example usage: obj.expected_results(phi) and returns: density_i,  density_i,  density_both,  expected_entropy,  expected_entropy,  mutual_info