def add_implicit_resolver(
    tag, regexp, first=None, Loader=None, Dumper=None, resolver=Resolver
):
    # type: (Any, Any, Any, Any, Any, Any) -> None
    """
    Add an implicit scalar detector.
    If an implicit scalar value matches the given regexp,
    the corresponding tag is assigned to the scalar.
    first is a sequence of possible initial characters or None.
    """
    if Loader is None and Dumper is None:
        resolver.add_implicit_resolver(tag, regexp, first)
        return
    if Loader:
        if hasattr(Loader, 'add_implicit_resolver'):
            Loader.add_implicit_resolver(tag, regexp, first)
        elif issubclass(
            Loader, (BaseLoader, SafeLoader, ruamel.yaml.loader.Loader, RoundTripLoader)
        ):
            Resolver.add_implicit_resolver(tag, regexp, first)
        else:
            raise NotImplementedError
    if Dumper:
        if hasattr(Dumper, 'add_implicit_resolver'):
            Dumper.add_implicit_resolver(tag, regexp, first)
        elif issubclass(
            Dumper, (BaseDumper, SafeDumper, ruamel.yaml.dumper.Dumper, RoundTripDumper)
        ):
            Resolver.add_implicit_resolver(tag, regexp, first)
        else:
            raise NotImplementedError

    Add an implicit scalar detector.
    If an implicit scalar value matches the given regexp,
    the corresponding tag is assigned to the scalar.
    first is a sequence of possible initial characters or None.
    
dynaconf/vendor/ruamel/yaml/main.py