def METHOD_NAME(self, mock_platform_info):
    mock_platform_info.return_value = {"switch_type": "npu"}
    assert device_info.is_chassis() == False
    assert device_info.is_voq_chassis() == False
    assert device_info.is_packet_chassis() == False
    mock_platform_info.return_value = {"switch_type": "voq"}
    assert device_info.is_voq_chassis() == True
    assert device_info.is_packet_chassis() == False
    assert device_info.is_chassis() == True
    mock_platform_info.return_value = {"switch_type": "chassis-packet"}
    assert device_info.is_voq_chassis() == False
    assert device_info.is_packet_chassis() == True
    assert device_info.is_chassis() == True
    mock_platform_info.return_value = {}
    assert device_info.is_voq_chassis() == False
    assert device_info.is_packet_chassis() == False
    assert device_info.is_chassis() == False