class_docstr: Handle to a markdown link, for easy existence test and printing
  (external links are not tested)
code: def __init__(
      self, root: Path, file: Path, name: str, link: str
  ) -> None:
      self.root = root
      self.file = file
      self.name = name
      self.link = link
  
file_path: submitit/submitit/test_documentation.py
imports: import re
  import typing
  from pathlib import Path
  import submitit
label_desc: Use image node_id 1 to create a new MarkdownLink object  with example: obj = MarkdownLink(root, file, name, link)