AutoComplete -> Combobox

AutoComplete -> Combobox

I wish to make input=text autocomplete, as here http://jqueryui.com/demos/autocomplete/#default, but with the button as here http://jqueryui.com/demos/autocomplete/#combobox
I.e. it is necessary for me that there was a dropping out list into which it is possible to enter any values, and not just those that are in the list.