code: def test_no_target(self):
      with pytest.raises(ValueError, match="The target cannot be None"):
          num_qubits = 1
  
          dev = qml.device("default.qubit", wires=num_qubits)
          observables = [qml.PauliZ(0)]
          loss = SquaredErrorLoss(rx_ansatz, observables, dev)
  
          phis = np.ones(num_qubits)
          loss(phis)
  
imports: import pytest
  import numpy
  import pennylane
  from pennylane.qnn.cost import SquaredErrorLoss
label_desc: Use image node_id 1 for calling the TestSquaredErrorLossJax obj's underlying member method code with example usage: obj.test_no_target() without return types