How to pass .ics file content in request body for calendar.events.insert to create event

[kala15]

How/can we pass standard .ics content as part of requestBody of "Content-Type": "text/calendar",

BEGIN:VCALENDAR
PRODID:-//Microsoft Corporation//Outlook 12.0 MIMEDIR//EN
VERSION:2.0
METHOD:PUBLISH
X-MS-OLK-FORCEINSPECTOROPEN:TRUE
BEGIN:VEVENT
CLASS:PUBLIC
DESCRIPTION:HOLIDAY\n
DTEND;VALUE=DATE:20090727
DTSTAMP:20091111T000000Z
DTSTART;VALUE=DATE:20090727
LAST-MODIFIED:20091111T000000Z
PRIORITY:5
SEQUENCE:0
SUMMARY;LANGUAGE=en-gb:HOLIDAY
END:VEVENT
END:VCALENDAR