Repository: home-assistant/core
File: homeassistant/components/vesync/sensor.py (Python)

Code before:
    value_fn: Callable[[VeSyncBaseDevice], StateType]

    exists_fn: Callable[[VeSyncBaseDevice], bool]


SENSORS: tuple[VeSyncSensorEntityDescription, ...] = (
    VeSyncSensorEntityDescription(
        key="filter-life",
        translation_key="filter_life",
        native_unit_of_measurement=PERCENTAGE,
        state_class=SensorStateClass.MEASUREMENT,
        entity_category=EntityCategory.DIAGNOSTIC,
        value_fn=lambda device: device.state.filter_life,
        exists_fn=lambda device: rgetattr(device, "state.filter_life") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="air-quality",
        translation_key="air_quality",
        value_fn=lambda device: device.state.air_quality_string,
        exists_fn=(
            lambda device: rgetattr(device, "state.air_quality_string") is not None
        ),
    ),
    VeSyncSensorEntityDescription(
        key="pm1",
        translation_key="pm1",
        device_class=SensorDeviceClass.PM25,
        native_unit_of_measurement=CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
        state_class=SensorStateClass.MEASUREMENT,
        value_fn=lambda device: device.state.pm1,
        exists_fn=lambda device: rgetattr(device, "state.pm1") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="pm10",
        translation_key="pm10",
        device_class=SensorDeviceClass.PM25,
        native_unit_of_measurement=CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
        state_class=SensorStateClass.MEASUREMENT,
        value_fn=lambda device: device.state.pm10,
        exists_fn=lambda device: rgetattr(device, "state.pm10") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="pm25",
        translation_key="pm25",
        device_class=SensorDeviceClass.PM25,
        native_unit_of_measurement=CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
        state_class=SensorStateClass.MEASUREMENT,
        value_fn=lambda device: device.state.pm25,
        exists_fn=lambda device: rgetattr(device, "state.pm25") is not None,
    ),
    VeSyncSensorEntityDescription(

Review comment (suggestion):
```suggestion
```
If you don’t set it (and the entity doesn’t override) it just used the device class default translation, which saves us extra translations 

Code after:
    value_fn: Callable[[VeSyncBaseDevice], StateType]

    exists_fn: Callable[[VeSyncBaseDevice], bool]


SENSORS: tuple[VeSyncSensorEntityDescription, ...] = (
    VeSyncSensorEntityDescription(
        key="filter-life",
        translation_key="filter_life",
        native_unit_of_measurement=PERCENTAGE,
        state_class=SensorStateClass.MEASUREMENT,
        entity_category=EntityCategory.DIAGNOSTIC,
        value_fn=lambda device: device.state.filter_life,
        exists_fn=lambda device: rgetattr(device, "state.filter_life") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="air-quality",
        translation_key="air_quality",
        value_fn=lambda device: device.state.air_quality_string,
        exists_fn=(
            lambda device: rgetattr(device, "state.air_quality_string") is not None
        ),
    ),
    VeSyncSensorEntityDescription(
        key="pm1",
        device_class=SensorDeviceClass.PM1,
        native_unit_of_measurement=CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
        state_class=SensorStateClass.MEASUREMENT,
        value_fn=lambda device: device.state.pm1,
        exists_fn=lambda device: rgetattr(device, "state.pm1") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="pm10",
        device_class=SensorDeviceClass.PM10,
        native_unit_of_measurement=CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
        state_class=SensorStateClass.MEASUREMENT,
        value_fn=lambda device: device.state.pm10,
        exists_fn=lambda device: rgetattr(device, "state.pm10") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="pm25",
        device_class=SensorDeviceClass.PM25,
        native_unit_of_measurement=CONCENTRATION_MICROGRAMS_PER_CUBIC_METER,
        state_class=SensorStateClass.MEASUREMENT,
        value_fn=lambda device: device.state.pm25,
        exists_fn=lambda device: rgetattr(device, "state.pm25") is not None,
    ),
    VeSyncSensorEntityDescription(
        key="power",
        translation_key="current_power",
        device_class=SensorDeviceClass.POWER,