curl --location --request POST 'https://www.googleapis.com/calendar/v3/freeBusy' \
--header 'Content-Type: application/json' \
--data-raw '{
"calendarExpansionMax": 0,
"groupExpansionMax": 0,
"items": [
{
"id": "string"
}
],
"timeMax": "2019-08-24T14:15:22.123Z",
"timeMin": "2019-08-24T14:15:22.123Z",
"timeZone": "UTC"
}'