How to use the @argdown/core.IArgument function in @argdown/core

return Object.keys(response.arguments).map((k) => {
            const argument = response.arguments[k];
            const title = argument.title;
            const item = vscode_languageserver_1.CompletionItem.create(`<${title}>`);
            item.textEdit = vscode_languageserver_1.TextEdit.replace(range, `<${title}>`);
            item.kind = vscode_languageserver_1.CompletionItemKind.Variable;
            const desc = core_1.IArgument.getCanonicalMemberText(argument);
            if (desc) {
                item.detail = desc;
            }
            return item;
        });
    }

exports.generateMarkdownForArgument = (argument) => {
    let relationsStr = "";
    if (argument.relations) {
        for (let relation of argument.relations) {
            const isOutgoing = relation.to === argument;
            const relationSymbol = getRelationSymbol(relation.relationType, isOutgoing);
            const relationPartner = isOutgoing ? relation.from : relation.to;
            const relationPartnerStr = relationPartner.type === core_1.ArgdownTypes.ARGUMENT ? `<${relationPartner.title}>` : `[${relationPartner.title}]`;
            relationsStr += `
  ${relationSymbol} ${relationPartnerStr}`;
        }
    }
    let desc = core_1.IArgument.getCanonicalMemberText(argument);
    if (desc) {
        desc = ":" + desc;
    }
    return `
\`\`\`argdown
<${argument.title}>${desc}${relationsStr}
\`\`\``;
};
const relationSymbols = {