How to pass multiple headers in Apollo GraphQI?

Question

I wanted to know how to pass multiple headers in Apollo GraphQl as i know how to pass single but not multiple headers.Any solutions or suggestions appreciated.Thanks in advance!

For suppose the below code is for single header how i can pass multiple headers in that way?

const authLink = setContext((_, { headers }) => {
  // get the authentication token from local storage if it exists
  const token = localStorage.getItem('token');
  // return the headers to the context so httpLink can read them
  return {
    headers: {
      ...headers,
      authorization: token ? `Bearer ${token}` : "",
    }
  }
});