code: def _handle_option_deprecations(options):
      
      undeprecated_options = _CaseInsensitiveDictionary()
      for key, value in iteritems(options):
          optname = str(key).lower()
          if optname in URI_OPTIONS_DEPRECATION_MAP:
              renamed_key = URI_OPTIONS_DEPRECATION_MAP[optname]
              if renamed_key.lower() in options:
                  warnings.warn("Deprecated option '%s' ignored in favor of "
                                "'%s'." % (str(key), renamed_key))
                  continue
              warnings.warn("Option '%s' is deprecated, use '%s' instead." % (
                            str(key), renamed_key))
          undeprecated_options[str(key)] = value
      return undeprecated_options
docs: Issue appropriate warnings when deprecated options are present in the
      options dictionary. Removes deprecated option key, value pairs if the
      options dictionary is found to also have the renamed option.