public static ArgumentFactory factory() {
        return new Factory();
    }
Returns an {@link ArgumentFactory} which understands Guava types.

<p>Currently supported types:</p>
<ul>
<li>{@code com.google.common.base.Optional}</li>
</ul>

@return an {@link ArgumentFactory} which understands Guava types.
guava/src/main/java/org/jdbi/v3/guava/GuavaArguments.java