def create_filter_alerts_creation_time(last_alert_fetched_time):
    """Create filter with the last alert fetched time to send in the request.

    Args:
        last_alert_fetched_time(date): Last date and time of alert that been fetched

    Returns:
        (str). The filter of alerts creation time that will be send in the  alerts list API request
    """
    filter_alerts_creation_time = f"alertCreationTime+gt+{last_alert_fetched_time.isoformat()}"

    if not filter_alerts_creation_time.endswith('Z'):
        filter_alerts_creation_time = filter_alerts_creation_time + "Z"

    return filter_alerts_creation_time