docs: def _locate_file(f, base_dir):
      """
      Utility method for finding full path to a filename as string
      """
      if base_dir == None:
          return f
      file_name = os.path.join(base_dir, f)
      real = os.path.realpath(file_name)
      #print_v('- Located %s at %s'%(f,real))
      return real