/**
 * Given a list of photos, return a set of unique tags present in all the photos.
 *
 * @param photos A list of dictionaries representing photos. Each dictionary contains a "tags" key which stores a list of tags for that photo.
 * @return A set containing unique tags present in all the photos.
 */
fun uniqueTags(photos: List<Map<String, List<String>>>): Set<String> {

    // Set comprehension to create a set of unique tags present in all the photos
    val uniqueTags = photos.flatMap { it["tags"] ?: emptyList() }.toSet()

    return uniqueTags
}
/**
 * Given a list of photos, return a set of unique tags present in all the photos.
 *
 * @param photos A list of dictionaries representing photos. Each dictionary contains a "tags" key which stores a list of tags for that photo.
 * @return A set containing unique tags present in all the photos.
 */
fun uniqueTags(photos: List<Map<String, List<String>>>): Set<String> {
/**
 * Given a list of photos, return a set of unique tags present in all the photos.
 *
 * @param photos A list of dictionaries representing photos. Each dictionary contains a "tags" key which stores a list of tags for that photo.
 * @return A set containing unique tags present in all the photos.
 */
fun uniqueTags(photos: List<Map<String, List<String>>>): Set<String> {

    // Set comprehension to create a set of unique tags present in all the photos
    val uniqueTags = photos.flatMap { it["tags"] ?: emptyList() }.toSet()

    return uniqueTags
}