def METHOD_NAME(features):
    features.default_features.append('anchor')
    """
    Registering the `anchor` feature, which uses the `Anchor` Draft.js entity type,
    and is stored as HTML with a `<a data-anchor>` tag.
    """
    feature_name = 'anchor'
    type_ = 'ANCHOR'
    control = {
        'type': type_,
        'label': '#',
        'description': 'Anchor',
    }
    features.register_editor_plugin(
        'draftail', feature_name, draftail_features.EntityFeature(
            control,
            js=[
                polyfills_js(),
                '/static/wagtailadmin/js/draftail.js',
                draftail_js(),
            ]
        )
    )
    features.register_converter_rule('contentstate', feature_name, {
        # Note here that the conversion is more complicated than for blocks and inline styles.
        'from_database_format': {'span[data-anchor]': anchor.AnchorEntityElementHandler(type_)},
        'to_database_format': {'entity_decorators': {type_: anchor.anchor_entity_decorator}},
    })