Small refactor and better comment

Author: tomer-w

custom_components/victron_mqtt/number.py

@@ -87,10 +87,11 @@ def __init__(
             installation_id,
         )
         self._attr_device_class = METRIC_TYPE_TO_DEVICE_CLASS.get(metric.metric_type)
-        if self._attr_device_class is not None:
-            self._attr_native_unit_of_measurement = metric.unit_of_measurement
-        elif metric.metric_type == MetricType.DYNAMIC:
-            # Dynamic units come from user-configured MQTT topics (e.g.
+        if self._attr_device_class is not None or metric.metric_type == MetricType.DYNAMIC:
+            # We need to set the _attr_native_unit_of_measurement in two cases:
+            # 1. When there known device class which support multiple units. In this case 
+            # we publish what we have and HA will allow convertion to other supported units.
+            # 2. Dynamic units come from user-configured MQTT topics (e.g.
             # SwitchableOutput Settings/Unit) and have no translation file
             # entry, so we must set the unit programmatically.
             self._attr_native_unit_of_measurement = metric.unit_of_measurement