'Return the state attributes.'

@property
def device_state_attributes(self):

    if self._supports_power_consumption:
        attrs = {ATTR_IN_USE: self._in_use, ATTR_LOAD_POWER: self._load_power, ATTR_POWER_CONSUMED: self._power_consumed}
    else:
        attrs = {}
    attrs.update(super().device_state_attributes)
    return attrs
