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ScriptedImporterAttribute.version

public int version;

Description

Importer version number that is used by the import layer to detect new version of the importer and trigger re-imports when such events occur, to apply latest changes made to the scripted imrpoter.

using UnityEngine;
using UnityEditor.AssetImporters;

[ScriptedImporter(1, "sphere")] public class SphereImporter : ScriptedImporter { public override void OnImportAsset(AssetImportContext ctx) { // ... } }