def METHOD_NAME(observable, key):
    g = cirq.PauliMeasurementGate(observable, key)
    assert g.num_qubits() == len(observable)
    assert g.key == 'a'
    assert g.mkey == cirq.MeasurementKey('a')
    assert g._observable == cirq.DensePauliString(observable)
    assert cirq.qid_shape(g) == (2,) * len(observable)