search returning a single from a suspend function

NetworkDataSourceImpl.kt

override fun search(token: String, query: String)
: Single<Either<Throwable, List<TweetApiModel>>>
= rxSingle {
    val response = twitterApi.search(requestsIOHandler.getTokenFormatted(token), query)
    if (requestsIOHandler.searchIsSuccessful(response)) {
       val tweets = requestsIOHandler.getTweets(response)
       Either.right(tweets)
    } else {
       Either.left(EmptyResponseException())
    }
}