code: function normalizeEvent(event) {
  		var source = event.source || {};
  		var ignoreTimezone = firstDefined(source.ignoreTimezone, options.ignoreTimezone);
  		event._id = event._id || (event.id === undefined ? '_fc' + eventGUID++ : event.id + '');
  		if (event.date) {
  			if (!event.start) {
  				event.start = event.date;
  			}
  			delete event.date;
  		}
  		event._start = cloneDate(event.start = parseDate(event.start, ignoreTimezone));
  		event.end = parseDate(event.end, ignoreTimezone);
  		if (event.end && event.end <= event.start) {
  			event.end = null;
  		}
  		event._end = event.end ? cloneDate(event.end) : null;
  		if (event.allDay === undefined) {
  			event.allDay = firstDefined(source.allDayDefault, options.allDayDefault);
  		}
  		if (event.className) {
  			if (typeof event.className == 'string') {
  				event.className = event.className.split(/\s+/);
  			}
  		}else{
  			event.className = [];
  		}
  		// TODO: if there is no start date, return false to indicate an invalid event
  	}
docs: /* Event Normalization
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