How to list all emails a Google calendar was shared with?

I would like to get all emails a google Calendar was shared with.

It seems to me that Calendar.CalendarList.list will not give me required info

/**
* Lists the calendars shown in the user's calendar list.
*/  
function listCalendars() {
  var calendars;
  var pageToken;
  do {
    calendars = Calendar.CalendarList.list({
      maxResults: 100,
      pageToken: pageToken
    });
    if (calendars.items && calendars.items.length > 0) {
      for (var i = 0; i < calendars.items.length; i++) {
        var calendar = calendars.items[i];
        Logger.log('%s (ID: %s)', calendar.summary, calendar.id);
      }
    } else {
      Logger.log('No calendars found.');
    }
    pageToken = calendars.nextPageToken;
  } while (pageToken);
}

Calendar.Acl.get(calId, "user:"+user) looks promising but I do not know how go get the info I want. Someone could help?

Suggestion

Perhaps you can try this sample script below that was derived from this similar post.

Sample Script

function aclTest(){
  calendarId = 'Calendar_ID';   
  calendars_acl_list = Calendar.Acl.list(calendarId);
  for (var i = 0; i < calendars_acl_list.items.length; i++) {
    var info = calendars_acl_list.items[i];
    if(info.role != "owner" && !info.id.includes("domain")){
      Logger.log(info.id);
    }
  }
}

Sample Test:

• Sample Test Calendar

• Apps Script result: