code: @CanIgnoreReturnValue
    public Ordered containsExactly(@NullableDecl Object k0, @NullableDecl Object v0, Object... rest) {
      return containsExactlyEntriesIn(accumulateMultimap(k0, v0, rest));
    }
docs: Fails if the multimap does not contain exactly the given set of key/value pairs.
  
  <p><b>Warning:</b> the use of varargs means that we cannot guarantee an equal number of
  key/value pairs at compile time. Please make sure you provide varargs in key/value pairs!