code: def discover_package_doc_dir(initial_dir):
      
      # Create an absolute Path to work with
      initial_dir = pathlib.Path(initial_dir).resolve()
  
      # Check if this is the doc/ dir already with a conf.py
      if _has_conf_py(initial_dir):
          return str(initial_dir)
  
      # Search for a doc/ directory in cwd (this covers the case of running
      # the CLI from the root of a repository).
      test_dir = initial_dir / 'doc'
      if test_dir.exists() and test_dir.is_dir():
          if _has_conf_py(test_dir):
              return str(test_dir)
  
      # Search upwards until a conf.py is found
      try:
          return str(_search_parents(initial_dir))
      except FileNotFoundError:
          raise
docs: Discover the ``doc/`` dir of a package given an initial directory.
  
      Parameters
      ----------
      initial_dir : `str`
          The inititial directory to search from. In practice, this is often the
          directory that the user is running the package-docs CLI from. This
          directory needs to be somewhere inside the package's repository.
  
      Returns
      -------
      root_dir : `str`
          The root documentation directory (``doc/``), containing ``conf.py``.
  
      Raises
      ------
      FileNotFoundError
          Raised if a ``conf.py`` file is not found in the initial directory,
          or any parents, or in a ```doc/`` subdirectory.