How to use the httpsnippet function in httpsnippet

async _generateCode(request, target, client) {
    // Some clients need a content-length for the request to succeed
    const addContentLength = (TO_ADD_CONTENT_LENGTH[target.key] || []).find(c => c === client.key);

    const { environmentId } = this.props;
    const har = await exportHarRequest(request._id, environmentId, addContentLength);
    const snippet = new HTTPSnippet(har);
    const cmd = snippet.convert(target.key, client.key);

    this.setState({ request, cmd, client, target });

    // Save client/target for next time
    window.localStorage.setItem('insomnia::generateCode::client', JSON.stringify(client));
    window.localStorage.setItem('insomnia::generateCode::target', JSON.stringify(target));
  }

async _handleCopyAsCurl(request) {
    const { activeEnvironment } = this.props;
    const environmentId = activeEnvironment ? activeEnvironment._id : 'n/a';
    const har = await exportHarRequest(request._id, environmentId);
    const snippet = new HTTPSnippet(har);
    const cmd = snippet.convert('shell', 'curl');
    clipboard.writeText(cmd);
  }

private refresh(record: DtoRecord, language: CodeSnippetLang, type: string) {
        const har = new HAR(record);
        let code = '';
        try {
            const snippet = new HTTPSnippet(har);
            code = snippet.convert(language, type);
        } catch (ex) {
            code = JSON.stringify(ex);
        }
        this.setState({ ...this.state, language, type, code });
    }