Registers a flag whose value can be a list of enum members.

Use the flag on the command line multiple times to place multiple enum values into the list.

name str, the flag name.
default Union[Iterable[Enum], Iterable[Text], Enum, Text, None], the default value of the flag; see DEFINE_multi; only differences are documented here. If the value is a single Enum, it is treated as a single-item list of that Enum value. If it is an iterable, text values within the iterable will be converted to the equivalent Enum objects.
enum_class class, the Enum class with all the possible values for the flag. help: str, the help message.
flag_values FlagValues, the FlagValues instance with which the flag will be registered. This should almost never need to be overridden.
module_name A string, the name of the Python module declaring this flag. If not provided, it will be computed using the stack trace of this call.
case_sensitive bool, whether to map strings to members of the enum_class without considering case.
**args Dictionary with extra keyword args that are passed to the Flag init.

a handle to defined flag.