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To import subcomponents click on 
icon on top of the component hierarchy. This will open a file selector dialog, you can either select a previously exported JSON file or select a handcrafted file. But it's its structure should match to the sample given above. Click on "Load" button to see a preview of import operation. Don't worry, you can still cancel operation after clicking on "Load". After clicking on "Load" following preview dialog will be displayed. Import operation will automatically create missing components, update existing components to match them to the information in JSON file. It will not delete any component even if it doesn't exist in the JSON file. But it will remove all component hierarchy and recreate it to match to the hierarchy specified in the JSON File.
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