prompt: Your task is to convert the following English description into an ASCII tree format.
  
  cms-contentful is a principal directory that includes 2 subdirectories: app and lib.
  At the main level, 'app' shelters 2 subdirectories that organize the source code.
  Within directory hierarchy 'app > api', 'api' encapsulates 3 subfolders: disable-draft, draft, revalidate.
  At level 3, in directory path 'app / api / disable-draft', 'disable-draft' has been left empty.
  Within directory hierarchy 'app → api → draft', Inside 'draft', you'll find it is devoid of content.
  At level 3, in directory path 'app / api / revalidate', Inside 'revalidate', you'll find it has nothing inside.
  Within directory hierarchy 'app / posts', 'posts' keeps 1 nested folders: [slug].
  In nested path 'app > posts > [slug]', '[slug]' contains no subdirectories.
  Back to the top level.
  At the top level, Inside 'lib', you'll find it is devoid of content.
  
  
  Format your response in this style:
  ```
  pre-compiled-headers
   +--groovy
   |   `--src
   |       +--hello
   |       |   +--cpp
   |       |   `--headers
   |       `--main
   |           `--cpp
   `--tests
  ```
  
  Provide your answer wrapped in <ascii_formatted> tags.
verification_info: {"ground_truth": "cms-contentful\n +--app\n |   +--api\n |   |   +--disable-draft\n |   |   +--draft\n |   |   `--revalidate\n |   `--posts\n |       `--[slug]\n `--lib", "description": "cms-contentful is a principal directory that includes 2 subdirectories: app and lib.\nAt the main level, 'app' shelters 2 subdirectories that organize the source code.\nWithin directory hierarchy 'app > api', 'api' encapsulates 3 subfolders: disable-draft, draft, revalidate.\nAt level 3, in directory path 'app / api / disable-draft', 'disable-draft' has been left empty.\nWithin directory hierarchy 'app \u2192 api \u2192 draft', Inside 'draft', you'll find it is devoid of content.\nAt level 3, in directory path 'app / api / revalidate', Inside 'revalidate', you'll find it has nothing inside.\nWithin directory hierarchy 'app / posts', 'posts' keeps 1 nested folders: [slug].\nIn nested path 'app > posts > [slug]', '[slug]' contains no subdirectories.\nBack to the top level.\nAt the top level, Inside 'lib', you'll find it is devoid of content.\n"}