How to add json-ld to header

Hi,

can you help me to add <script type=”application/ld+json”> to the header in a single-event-page? <script> tags get deleted, when I save the edits. So how can I add some stuff like json-ld to the single event output? I want to add special tags for google knowledge graph … see below

<script type="application/ld+json"> 
{
  "@context": "https://www.schema.org",
  "@type": "Event",
  "name": "#_EVENTNAME",
  "url": "#_EVENTPAGEURL",
  "description": "#_EXCERPT",
  "startDate": "#_STARTDATE{Y-m-d}T#_24HSTARTTIME",
  "endDate": "#_ENDDATE{Y-m-d}T#_24HENDTIME",
  "location": {
    "@type": "Place",
    "name": "#_LOCATION",
    "address": {
      "@type": "PostalAddress",
      "streetAddress": "#_ADDRESS",
      "addressLocality": "#_CITY",
      "postalCode": "#_ZIP",
      "addressCountry": "#_COUNTRY"
    }
  },
}
 </script>