public static Executor newInstance(final CloseableHttpClient httpclient) {
        return new Executor(httpclient != null ? httpclient : GET_CLASSIC_CLIENT());
    }
Executor for {@link Request}s.
<p>
A connection pool with maximum 100 connections per route and
a total maximum of 200 connections is used internally.

@since 4.2
httpclient5-fluent/src/main/java/org/apache/hc/client5/http/fluent/Executor.java