code: def make_variant(cls, converters, re_opts=None, compiled=False, strict=True):
          assert converters, "REQUIRE: Non-empty list."
          if len(converters) == 1:
              return converters[0]
          if re_opts is None:
              re_opts = cls.default_re_opts
          pattern = r")|(".join([tc.pattern for tc in converters])
          pattern = r"("+ pattern + ")"
          group_count = len(converters)
          for converter in converters:
              group_count += pattern_group_count(converter.pattern)
          if compiled:
              convert_variant = cls.__create_convert_variant_compiled(converters,
                                                                  re_opts, strict)
          else:
              convert_variant = cls.__create_convert_variant(re_opts, strict)
          convert_variant.pattern = pattern
          convert_variant.converters = tuple(converters)
          convert_variant.regex_group_count = group_count
          return convert_variant