def METHOD_NAME():
    dp = cirq.depolarize(0.1)
    kc = cirq.KrausChannel.from_channel(dp)
    with pytest.raises(TypeError):
        _ = cirq.measurement_key_name(kc)
    assert cirq.with_measurement_key_mapping(kc, {'a': 'b'}) is NotImplemented
    kc_x = cirq.KrausChannel.from_channel(dp, key='x')
    assert cirq.with_measurement_key_mapping(kc_x, {'a': 'b'}) is kc_x
    assert cirq.measurement_key_name(cirq.with_key_path(kc_x, ('path',))) == 'path:x'
    kc_a = cirq.KrausChannel.from_channel(dp, key='a')
    kc_b = cirq.KrausChannel.from_channel(dp, key='b')
    assert kc_a != kc_b
    assert cirq.with_measurement_key_mapping(kc_a, {'a': 'b'}) == kc_b