code: @SafeVarargs
      public static <T> Predicate<T> in(@Nonnull T first, @Nonnull T... rest) {
          Collection<T> allowed = ImmutableList.<T>builder()
                  .add(first)
                  .add(rest)
                  .build();
  
          return Predicates.in(allowed);
      }
docs: Predicate that returns true when input value is memeber of set consisting of {@code first} and {@code rest}
  
  @param first element
  @param rest  of the elements
  @param <T>   type of elements
  @return the in predicate