How to use the netlify-identity-widget.open function in netlify-identity-widget

        <button type="button"> netlifyIdentity.open("signup")}&gt;
          Signup</button>

login () {
        netlifyIdentity.open('login')
    }
  }

handleLogin = type => () => {
    netlifyIdentity.open(type);
  };
  render() {

return new Promise((resolve, reject) => {
        if (isLoggedIn()) {
            resolve();
        } else {
            netlifyIdentity.open();
            netlifyIdentity.on('login', user => {
                netlifyIdentity.close();
                resolve();
            });
        }
        netlifyIdentity.on('error', err => {
            reject(err);
        });
    });
}

          onClick={() => netlifyIdentity.open("login")}
        >

authenticate = ({ showSignup = false, onSuccess }) => {
    netlifyIdentity.open(showSignup && 'signup');
    netlifyIdentity.on('login', user => {
      this.setState({ user });
      onSuccess && onSuccess(user);
    });
  };