FILE: main.kt
    public final typealias ImmutableMap<K, V> = R|imm/Map<K, V>|
    public final typealias ImmutableSet<E> = R|imm/Set<E>|
    public final typealias ImmutableLinkedHashSet<E> = R|imm/LinkedHashSet<E>|
    private final typealias ImmutableMultimap<K, V> = R|{ImmutableMap<K, ImmutableSet<V>>=} imm/Map<K, ImmutableSet<V>>|
    private final fun <K, V> R|{ImmutableMultimap<K, V>=} imm/Map<K, ImmutableSet<V>>|.put(key: R|K|, value: R|V|): R|kotlin/Unit| {
        this@R|/put|.R|SubstitutionOverride<imm/Map.get: R|imm/Option<ImmutableSet<V>!>!|>|(R|<local>/key|).R|SubstitutionOverride<imm/Option.getOrElse: R|ImmutableSet<V>!|>|(Q|ImmutableLinkedHashSet|.R|imm/LinkedHashSet.empty*s|<R|V|>())
    }
