amazon_uam_sample_config for header.

amazon_uam_sample_config.js

// Load APS library
  !function(a9,a,p,s,t,A,g){if(a[a9])return;function q(c,r){a[a9]._Q.push([c,r])}a[a9]={init:function(){q("i",arguments)},fetchBids:function(){q("f",arguments)},setDisplayBids:function(){},targetingKeys:function(){return[]},_Q:[]};A=p.createElement(s);A.async=!0;A.src=t;g=p.getElementsByTagName(s)[0];g.parentNode.insertBefore(A,g)}("apstag",window,document,"script","//c.amazon-adsystem.com/aax2/apstag.js");

  apstag.init({
    pubID: 'pub_id_amazon_uam',
    adServer: 'googletag',
    simplerGPT: true
  });

  var googletag = googletag || {};
  googletag.cmd = googletag.cmd || [];

  var slot1;

  googletag.cmd.push(function() {
    var mapping_atf = googletag.sizeMapping().
      addSize([735, 500], [728, 90]).
      addSize([0, 0], [320, 50]).
      build();

    slot1 = googletag.defineSlot('/dfp_account_id/ad_unit_1', [[728, 90], [320, 50]], 'div-gpt-ad-xxxxxxxxxx-0').defineSizeMapping(mapping_atf).addService(googletag.pubads());


  googletag.pubads().disableInitialLoad();
  googletag.pubads().enableSingleRequest();
  googletag.pubads().collapseEmptyDivs();
  googletag.enableServices();
});

  googletag.cmd.push(function(){
    apstag.fetchBids({
    timeout: 2000 },
      function(bids) {
        apstag.setDisplayBids();
        googletag.pubads().refresh();
    });
  });
</script>