class_docstr: Handle to a markdown link, for easy existence test and printing
  (external links are not tested)
code: def exists(self) -> bool:
      if self.link.startswith("http"):
          # We don't check external urls.
          return True
      link = self.link.split("#")[0]
      if not link:
          return False
      fullpath = self.root / self.file.parent / link
      return fullpath.exists()
  
file_path: submitit/submitit/test_documentation.py
imports: import re
  import typing
  from pathlib import Path
  import submitit
label_desc: Use image node_id 2 for calling the MarkdownLink obj's underlying member method code with example usage: obj.exists() and returns: fullpath, True, False