A BlockEditorTemplate object looks like:

{
  // the ID of the page
  "id": 1,
  // name of the template
  "name": "Navigation Bar",
  // description of the template
  "description": "A bar of links to other content",
  // the creation date for the template
  "created_at": "2012-08-06T16:46:33-06:00",
  // the date the template was last updated
  "updated_at": "2012-08-08T14:25:20-06:00",
  // The JSON data that is the template
  "node_tree": null,
  // The version of the editor that created the template
  "editor_version": "1.0",
  // The type of template. One of 'block', 'section', or 'page'
  "template_type": "page",
  // String indicating what state this assignment is in.
  "workflow_state": "unpublished"
}