How does one set global headers in axios?

Hi I'm setting default axios headers in request interceptor but these headers are not accessible in another function... in axios axios documentation it is mentioned that global-axios-defaults are global...below is my sample code need help

axios.interceptors.request.use(function (config) {
  axios.defaults.headers.accesstoken= "some_access_token"
  axios.defaults.headers.client = "some_client"
  axios.defaults.headers.uid = "some_uid"
  return config;
},function (error) {
  return Promise.reject(error);
});

On page load componentDidmount executes but axios default headers are undefined in this function

componentDidMount: function() {
  console.log(axios.defaults.headers) #its giving me undefined
  axios.get("http://some_url_for_get_request.json", {
    headers: {
      accesstoken: axios.defaults.headers.accesstoken,
       uid: axios.defaults.headers.uid,
       client: axios.defaults.headers.client
    }
  })
}

You can set the default Custom Headers in Axios for every XHR call like this:

axios.defaults.headers.common = {
  "X-Requested-With": "XMLHttpRequest",
  "X-CSRFToken": "example-of-custom-header"
};

You can also add configurations onward like this:

  window.axios.defaults.headers.post['xsrfCookieName'] = 'CSRFToken';
  window.axios.defaults.headers.post['xsrfHeaderName'] = 'X-CSRFToken';
  window.axios.defaults.headers.post['responseType'] = 'json';
  window.axios.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded';