code: def _find_egg_info(ireq):
      
      root = ireq.setup_py_dir
  
      directory_iterator = _iter_egg_info_directories(root, ireq.name)
      try:
          top_egg_info = next(directory_iterator)
      except StopIteration:   # No egg-info found. Wat.
          return None
      directory_iterator = itertools.chain([top_egg_info], directory_iterator)
  
      # Read the sdist's PKG-INFO to determine which egg_info is best.
      pkg_info = _read_pkg_info(root)
  
      # PKG-INFO not readable. Just return whatever comes first, I guess.
      if pkg_info is None:
          return top_egg_info
  
      # Walk the sdist to find the egg-info with matching PKG-INFO.
      for directory in directory_iterator:
          egg_pkg_info = _read_pkg_info(directory)
          if egg_pkg_info == pkg_info:
              return directory
  
      # Nothing matches...? Use the first one we found, I guess.
      return top_egg_info
docs: Find this package's .egg-info directory.
  
      Due to how sdists are designed, the .egg-info directory cannot be reliably
      found without running setup.py to aggregate all configurations. This
      function instead uses some heuristics to locate the egg-info directory
      that most likely represents this package.
  
      The best .egg-info directory's path is returned as a string. None is
      returned if no matches can be found.