code: def expected_fidelity_rx_pauliz(param):
      """Return the analytical fidelity for the RX and PauliZ."""
      return (np.cos(param / 2)) ** 2
  
imports: import pytest
  import pennylane
  from pennylane import numpy
label_desc: Use image node_id 1 for calling a global function with example usage: expected_fidelity_rx_pauliz(param) and returns: unknown