code: def create_type_variants(cls, type_names, type_dict):
          
          type_variant_dict = {}
          for type_name in type_names:
              type_variant = cls.create_type_variant(type_name, type_dict)
              type_variant_dict[type_name] = type_variant
          return type_variant_dict
docs: Create type variants for types with a cardinality field.
          The new type converters are based on the type converter with
          cardinality=1.
  
          .. code-block:: python
  
              # -- USE: parse_number() type converter function.
              new_types = CardinalityFieldTypeBuilder.create_type_variants(
                              ["Number?", "Number+"], dict(Number=parse_number))
  
          :param type_names: List of type names with cardinality field suffix.
          :param type_dict:  Type dictionary with named type converters.
          :return: Type dictionary with type converter variants.