docs: def makemap(filenames, sourcedir, targetdir=None):
  
      """Return an OrderedDict (to preserve script run order) which maps
      filenames coming from a single local source directory to a single
      target directory.  Most useful for scripts, whose location when
      run is often unimportant, and so can all be placed in common
      directory."""
  
      if targetdir is None: targetdir = DEFAULT_TARGETDIR
      return OrderedDict(
          (join(targetdir, f),  join(sourcedir, f)) for f in filenames)