def add_multi_constructor(tag_prefix, multi_constructor, Loader=None, constructor=Constructor):
    # type: (Any, Any, Any, Any) -> None
    """
    Add a multi-constructor for the given tag prefix.
    Multi-constructor is called for a node if its tag starts with tag_prefix.
    Multi-constructor accepts a Loader instance, a tag suffix,
    and a node object and produces the corresponding Python object.
    """
    if Loader is None:
        constructor.add_multi_constructor(tag_prefix, multi_constructor)
    else:
        if False and hasattr(Loader, 'add_multi_constructor'):
            Loader.add_multi_constructor(tag_prefix, constructor)
            return
        if issubclass(Loader, BaseLoader):
            BaseConstructor.add_multi_constructor(tag_prefix, multi_constructor)
        elif issubclass(Loader, SafeLoader):
            SafeConstructor.add_multi_constructor(tag_prefix, multi_constructor)
        elif issubclass(Loader, ruamel.yaml.loader.Loader):
            Constructor.add_multi_constructor(tag_prefix, multi_constructor)
        elif issubclass(Loader, RoundTripLoader):
            RoundTripConstructor.add_multi_constructor(tag_prefix, multi_constructor)
        else:
            raise NotImplementedError

    Add a multi-constructor for the given tag prefix.
    Multi-constructor is called for a node if its tag starts with tag_prefix.
    Multi-constructor accepts a Loader instance, a tag suffix,
    and a node object and produces the corresponding Python object.
    
dynaconf/vendor/ruamel/yaml/main.py