Add multiple li to ul at once with Javascript [duplicate]

Scenario:

I have an HTML unordered list.

I have a button that triggers an AJAX call that returns an HTML string that is a bunch of <li>...</li> elements in plain text.

I want to add that bunch of li elements to the ul with Javascript.

What I know:

I know I can do something like:

newLi = document.createElement("li");
document.getElementById('#the_ul').appendChild(newLi);

But I don't know how to do something like:

newBunchOfLis = createThemFromHTML('<li>hello</li><li>bye</li>');
document.getElementById('#the_ul').appendChild(newBunchOfLis);

Question:

What do you suggest?